Tagged digital data-encoding nucleic acid and method for producing a tagged digital data-encoding nucleic acid

Abstract

Tagged digital data-encoding nucleic acid and method for producing a tagged digital data-encoding nucleic acid A tagged digital data-encoding nucleic acid comprising: (a) at least one digital data-encoding nucleic acid encoding digital data; and (b) at least one taggant that is attached to selected nucleotides, wherein the taggant attached to the selected nucleotides is detectable using a detection unit.

Description

TAGGED DIGITAL DATA-ENCODING NUCLEIC ACIDAND METHOD FOR PRODUCINGA TAGGED DIGITAL DATA-ENCODING NUCLEIC ACID

[0001] The present invention is directed at a tagged digital data-encoding nucleic acid. The present invention is further directed at a method for producing the tagged digital data-encoding nucleic acid, an object having the tagged digital data-encoding nucleic acid and a method for authenticating the object.

[0002] With the recent progress made in the field of DNA synthesis and DNA sequencing, DNA is becoming a new candidate for storing digital data and / or for marking objects for authentication purposes. A main challenge with the use of DNA for digital data storage and / or marking purposes is to ensure that the DNA was issued, synthetized and / or produced by a legitimate issuer, i.e. that the DNA was not produced, copied, modified or issued by a fraudster.

[0003] An objective of the present invention is the provision of an improved nucleic acid and of an improved method for producing the same.SUMMARY OF THE INVENTION

[0004] According to a first aspect, a tagged digital data-encoding nucleic acid is provided, said tagged digital data-encoding nucleic acid comprising:

[0005] (a) at least one digital data-encoding nucleic acid encoding digital data; and

[0006] (b) at least one taggant that is attached to selected nucleotides, wherein the taggant attached to the selected nucleotides is detectable using a detection unit.

[0007] According to a second aspect, the invention provides a tagged digital data-encoding deoxyribonucleic acid (1) (DNA), comprising:

[0008] at least one digital data-encoding DNA (2) encoding digital data (4), wherein the digital data-encoding DNA comprises:

[0009] a strand comprisingmDNA service blocks ofnnucleotides, wherein at least 2 of the DNA service blocks independently encode digital data, andmis from 2 to 250, andnis from 2 to 250;

[0010] each DNA service block being linked to its following DNA service block by a fusion sequence, the fusion sequence consisting of at least three nucleotides, which fusion sequence is invariant, and the fusion sequence is absent from the DNA service blocks; and

[0011] at least one DNA service block bears at least one taggant which is a methylated nucleotide, at a DNA methyl transferase recognition site.

[0012] The digital data-encoding nucleic acid is a nucleic acid, more particularly a single or double-stranded DNA or RNA molecule, which encodes digital data in a sequence of nucleotides. Preferably, the tagged digital data-encoding nucleic acid is provided as a double-stranded and / or circular DNA sequence (such as plasmids) to limit degradation and allow its biological replication / amplification. Further, synthesized double-stranded nucleic acids can have a much longer length than single-stranded nucleic acids, making the former more adapted to encode digital data.

[0013] “Digital data” refers to data that can be managed by computerized machines. As used herein, the expression “digital data” refers to data which can be represented by a binary system. As used herein, a “binary system” refers to a language composed of bits “0” and “1”. Non-limitative examples of digital data may be program files, text files, music files, image files, video files, encrypted files and combinations thereof. The digital data is preferably human or computer-generated. In particular, the digital data does not include any data encoding any known full-length proteins.

[0014] Preferably, the digital data-encoding nucleic acid is biocompatible. “Biocompatible” refers to the ability to be handled (such as to be replicated and manipulated) by a living organism. Preferably, the digital data-encoding nucleic acid includes multiple stop-codons in all (preferably 6) reading frames and the absence of the majority of the start codons, to ensure that the digital data-encoding nucleic acid do not inadvertently or intentionally cause harm to human health, agriculture, and the environment, notably to protect against bioterrorism, biocrime, and other forms of biological aggression.

[0015] The word “tagged” (in particular in the expression “tagged digital data-encoding nucleic acid”) indicates that the digital data-encoding nucleic acid comprises a taggant (which is a label), wherein it is the nucleic acid that is tagged, not the digital data. The taggant is preferably only attached to selected nucleotides, wherein the selected nucleotides have a specific property. For example, the selected nucleotides are specific purine or pyrimidine bases provided in a specific sequence of nucleotides to which the taggant reacts. The taggant can be attached to the selected nucleotides according to a taggant pattern that is in particular only achievable by the authentic issuer of the tagged digital data-encoding nucleic acid, for example by using specifically designed bacteria. This provides for an anti-copy protection of the tagged digital data-encoding nucleic acid. In some embodiments, the taggant pattern is kept private, so that only the authentic issuer knows it. The taggant pattern is in particular very difficult to reproduce by someone else than the authentic issuer.

[0016] That the taggant is detectable using a detection unit (for example during sequencing of the tagged digital data-encoding nucleic acid) in particular means that by detecting the taggant, the selected nucleotides can be identified. The “detection unit” can designate any device (hardware and / or software based) which can perform sequencing and / or characterization of the taggant pattern. The presence of the taggant on the expected selected nucleotides can be indicative of whether the tagged digital data-encoding nucleic acid is authentic. In other words, nobody except the legitimate issuer of the tagged digital data-encoding nucleic acid can claim to be the legitimate issuer thereof (or only very difficultly as the fraudster would have to also reproduce the very specific taggant pattern). Thus, the tagged digital data-encoding nucleic acid allows storing the digital data and protecting it from being copied or modified by fraudsters. The taggant further acts as a copyright proof for the digital data.

[0017] In one embodiment,nis 2-100, preferably 2-80, more preferably 2-50, more particularly preferably 2-10, alternativelynis 2-4, particularly 4.

[0018] In a preferred embodiment of the tagged digital data-encoding DNA of the invention,nis invariant, that is the number of nucleotides in the DNA service blocks is the same in all DNA service blocks.

[0019] In another embodiment,nis invariant andnis 2-100, preferably 2-80, more preferably 2-50, more particularly preferably 2-10, alternativelynis 2-4, particularly 4.

[0020] In another embodiment of the tagged digital data-encoding DNA according to the invention, the fusion sequence consists of at least 4 nucleotides, in particular 4 to 50 nucleotides, 4 to 40 nucleotides, 4 to 30 nucleotides, 4 to 20 nucleotides or 4 to 10 nucleotides, preferably it consists of 4 nucleotides.

[0021] In another embodiment of the tagged digital data-encoding DNA according to the invention, the fusion sequences comprise a stop codon.

[0022] In another embodiment of the tagged digital data-encoding DNA according to the invention, the fusion sequence comprises the sequence TTAG.

[0023] In another embodiment of the tagged digital data-encoding DNA according to the invention,mis from 2 to 250, preferably 2 to 70, more preferably 4 to 30, more particularly preferably 4 to 20. In one embodiment,mis 18.

[0024] In another embodiment of the invention,nis invariant andnis 2-100, preferably 2-80, more preferably 2-50, more particularly preferably 2-10, alternativelynis 2-4, particularly 4, and the fusion sequence consists of at least 4 nucleotides, preferably it consists of 4 nucleotides.

[0025] In another embodiment of the invention,nis invariant andnis 2-4, more preferably n is 4, and the fusion sequence consists of at least 4 nucleotides, preferably it consists of 4 nucleotides, and the fusion sequences comprise a stop codon.

[0026] In another embodiment of the invention, about 2 to about 75% of the DNA service blocks bear at least one methylated nucleotide, preferably about 2 to about 50% of the DNA service blocks bear at least one methylated nucleotide.

[0027] In another embodiment of the invention, some DNA service blocks bear one, two, three, four or more, and up to 50 methylated nucleotides.

[0028] The fusion sequences may bear at least one methylated nucleotide at a DNA methyltransferase recognition site, in which case all fusion sequences are methylated.

[0029] In one embodiment,mis 2 to 30, and the tagged digital data-encoding DNA bears 2 to 8 methylated nucleotides. In another embodiment, m is 2 to 24, preferably 18, and the tagged digital data-encoding DNA bears 2 to 4 methylated nucleotides.

[0030] The methylated nucleotides are at DNA methyl transferase recognition sites. DNA methyl transferase recognition sites are well-known in the art. Some examples are given in the Table below:Examples of DNA methyl transferases and their recognition sitesEnzymeOrganismRecognitionsequenceModificationTypeDam (M.EcoDam)Escherichia coliGATC6mAOrphan (Type II-like A-MTase)Dcm (M.EcoDcm)Escherichia coliCCWGG5mCC5-MTase (Type II)CcrM (M.CcrM)Caulobacter crescentus (Alphaproteobacteria)GANTC6mAOrphan A-MTaseM.EcoRIEscherichia coli (EcoRI RM)GAATTC6mAType II (RM)M.EcoRVEscherichia coli (EcoRV RM)GATATC6mAType II (RM)M.PstIProvidencia stuartii (PstI RM)CTGCAG6mAType II (RM)M.BamHIBacillus amyloliquefaciens (BamHI RM)GGATCC4mCType II (RM)M.BglIIBacillus globigii (BglII RM)AGATCT5mCType II (RM)M.KpnIKlebsiella pneumoniae (KpnI RM)GGTACC6mAType II (RM)M.AluIArthrobacter luteus (AluI RM)AGCT5mCType II (RM)M.HpaIIHaemophilus parainfluenzae (HpaII RM)CCGG (inner C)5mCType II (RM)M.MspIMoraxella sp. (MspI RM)CCGG (outer C)5mCType II (RM)M.HhaIHaemophilus haemolyticus (HhaI RM)GCGC5mCType II (RM)M.TaqIThermus aquaticus (TaqI RM)TCGA6mAType II (RM)M.MboIMoraxella bovis (MboI RM)GATC6mAType II (RM)M.DpnII (M.DpnM)Diplococcus pneumoniae (DpnII RM)GATC6mAType II (RM)M.Sau3AIStaphylococcus aureus (Sau3AI RM)GATC6mAType II (RM)M.PvuIIProteus vulgaris (PvuII RM)CAGCTG (inner C)4mCType II (RM)M.HaeIIIHaemophilus aegyptius (HaeIII RM)GGCC5mCType II (RM)M.EcoRIIEscherichia coli (EcoRII RM)CCWGG (inner C)5mCType II (RM)M.SssISpiroplasma sp.CG5mCC5-MTase (CpG)M.BstUIBacillus stearothermophilus (BstUI RM)CGCG5mCType II (RM)M.MluIMicrococcus luteus (MluI RM)ACGCGT5mCType II (RM)M.EagIEnterobacter aerogenes (EagI RM)CGGCCG5mCType II (RM)M.BssHIIBacillus sphaericus (BssHII RM)GCGCGC5mCType II (RM)M.NotINocardia otitidiscaviarum (NotI RM)GCGGCCGC5mCType II (RM)M.NruINocardia rubra (NruI RM)TCGCGA5mCType II (RM)M.HindIIIHaemophilus influenzae (HindIII RM)AAGCTT6mAType II (RM)M.XbaIXanthomonas badrii (XbaI RM)TCTAGA5mC / 6mA (varies by MTase class)Type II (RM)M.NheINeisseria haemolytica (NheI RM)GCTAGC5mC / 6mA (varies)Type II (RM)M.SpeISerratia marcescens (SpeI RM)ACTAGT6mAType II (RM)M.SacIStreptomyces achromogenes (SacI RM)GAGCTC5mCType II (RM)M.SacIIStreptomyces achromogenes (SacII RM)CCGCGG5mCType II (RM)M.AvrIIAnabaena variabilis (AvrII RM)CCTAGG5mCType II (RM)M.ApaIAcetobacter pasteurianus (ApaI RM)GGGCCC5mCType II (RM)M.AatIIAcetobacter acetii (AatII RM)GACGTC5mCType II (RM)M.NdeINeisseria denitrificans (NdeI RM)CATATG6mAType II (RM)M.SphIStreptomyces phaeochromogenes (SphI RM)GCATGC6mAType II (RM)M.BspHIBacillus species (BspHI RM)TCATGA6mAType II (RM)M.HincIIHaemophilus influenzae (HincII RM)GTYRAC5mCType II (RM)M.PciIPseudomonas citrii (PciI RM)ACATGT6mAType II (RM)M.SnaBISphaerotilus natans (SnaBI RM)TACGTA5mCType II (RM)M.BspDIBacillus sp. (BspDI RM)ATCGAT5mCType II (RM)M.EcoKIEscherichia coli K12 (Type I RM EcoKI)AACNNNNNNGTGC (bipartite)6mAType I (RM)M.EcoR124IEscherichia coli (Type I RM EcoR124I)GAANNNNNNRTCG (bipartite)6mAType I (RM)M.BsrBIBacillus sphaericus (BsrBI RM)CCGCTC5mCType II (RM)M.SfcIStreptomyces ferus (SfcI RM)CTRYAG5mCType II (RM)M.AciIArthrobacter citreus (AciI RM)CCGC5mCType II (RM)M.BglIBacillus globigii (BglI RM)GCCNNNNNGGC5mCType II (RM)M.BbvCIBacillus brevis (BbvCI RM)CCTCAGC5mCType IIB (RM)M.SfiIStreptomyces fimicarius (SfiI RM)GGCCNNNNNGGCC5mCType II (RM)M.AspBHIAspergillus (bacterial-like usage)YSCNS5mCMspJI-family-likeM.CviPIChlorella virus (algal virus)GpC (GC)5mCViral C5-MTaseDam (M.EcoP1Dam)Bacteriophage P1GATC6mAPhage-encoded orphanM.HvoCTAG (putative HVO_0794)Haloferax volcaniiCTAG (as Cm4TAG)4mCType II (RM) candidateM.Hvo-GCA-N6-VTGCHaloferax volcaniiGCAN6VTGC6mAType I (RM) candidateM.BsaAIBacillus stearothermophilus (BsaAI RM)YACGTR5mCType II (RM)M.AciBI (AciI isoschiz.)Arthrobacter sp.CCGC5mCType II (RM)M.BseRIBacillus stearothermophilus (BseRI RM)GAGGAG6mA / 5mC (varies)Type II (RM)M.BpuEIBacillus pumilus (BpuEI RM)CTTGAG5mCType IIB (RM)M.HpyAVHelicobacter pyloriCCTTC5mCType II (RM)M.Hpy99IIIHelicobacter pylori 99GAGTC6mAType II (RM)M.NlaIIINeisseria lactamica (NlaIII RM)CATG6mAType II (RM)M.BfaIBacillus fastidiosus (BfaI RM)CTAG4mC / 5mC (varies)Type II (RM)M.TthHB27IThermus thermophilusCGATCG5mCType II (RM)M.BsaHIBacillus stearothermophilus (BsaHI RM)GRCGYC5mCType II (RM)M.SmlIStreptomyces mobaraensis (SmlI RM)CTYRAG5mCType II (RM)M.BspEIBacillus species (BspEI RM)TCCGGA5mCType II (RM)M.HinP1IHaemophilus influenzae (HinP1I RM)GCGC5mCType II (RM)M.BisI (M.CviPII-like)Bacillus speciesGCNGC (methylation-dependent RE context)5mCMethylation-dependent

[0031] In a preferred embodiment, methylation is at a site selected from BsrBIM, SfcIM and AciIM, and one or more of these sites.

[0032] According to an embodiment, the tagged digital data-encoding nucleic acid is configured to form a security marking associated with an object for authenticating the object, wherein:

[0033] the digital data includes an object information describing the object and / or a representation of the object information.

[0034] The tagged digital data-encoding nucleic acid is part of a security marking associated with an object. “Associated” here means that it is either physically attached to the object, deposited on the object, encapsulated in the object, or otherwise related to the object through the content of the digital information belonging to the object. To associate the tagged digital data-encoding nucleic acid to the object, the tagged digital data-encoding nucleic acid can be encapsulated in a suitable substrate (such as chitosan or silica) to use it in different forms (films, gels, wires, powder, etc.), thereby protecting the tagged digital data-encoding nucleic acid against degradations during aging. The object can be any type of physical object, including printed documents, packaging materials or specific parts of a complex multi-part object. In particular, the object is a valuable object or good. The object may also be a digital document to which the tagged digital data-encoding nucleic acid is associated. In the case in which the security marking is related to the object through the content of the digital information belonging to the object, the tagged digital data-encoding nucleic acid may be provided separately from the object that it is describing and / or protecting. For example, a printed property certificate may include a tagged digital data-encoding nucleic acid indicating that a house at a specific address and / or GPS location belongs to a specific owner, wherein the tagged digital data-encoding nucleic acid is not provided on the house, but rather on the printed document.

[0035] The object information can include any information describing the object, such as an identification information, a fingerprint, a GPS location, and / or a serial number for uniquely identifying the object, a date and / or place of production of the object, an identification information of the issuer of the object information, physical, chemical and / or biological characteristics of the object, or the like. The representation of the object information can be an encrypted, hashed or otherwise transformed representation of the object information. Since the digital data includes a unique object information relating to the given object (e.g. unique fingerprint, serial number or the like), the security marking cannot be used for any other object, making it more secure.

[0036] It can be proven that the object is authentic by associating the security marking comprising the tagged digital data-encoding nucleic acid with the object. By decoding the tagged digital data-encoding nucleic acid, the object information can be retrieved, and by verifying the position and / or pattern of the taggant in the tagged digital data-encoding nucleic acid, it is guaranteed that the tagged digital data-encoding nucleic acid (and hence the object) is genuine. A more secure and reliable security marking is thus provided.

[0037] According to a further embodiment, the taggant includes:

[0038] a chemical marker chemically modifying the selected nucleotides; and / or

[0039] an isotopic marker.

[0040] Chemical markers can be additions of chemical compounds to the selected nucleotides. Examples for chemical markers are provided below. Isotopic markers can be markers that replace specific atoms in the nucleotides forming the digital data-encoding nucleic acid by an isotope thereof.

[0041] According to a further embodiment, the chemical modification includes: methylation, hydroxymethylation, formylation, carboxylation, glycosylation, alkylation, phosphorylation, base excision, base chemical modification, colorimetric marking and / or fluorescent marking.

[0042] In particular, the chemical modification is an epigenetic modification. The nucleotides may also be modified by adjunction of specific molecules, such as biotin or digoxigenin, which are further examples for chemical modifications and can be detected by immunochemistry. The “tagging” is in particular performed during the synthesis of the nucleic acid sequence, using modified nucleotides or modified DNA fragments. The modified nucleotides (fluorophore, isotope, biotin, digoxigenin, etc.) are compatible with enzyme activity necessary for the DNA synthesis or assembly (DNA polymerases, endonucleases). Detection of taggants can for instance be achieved by performing nanopore DNA / RNA sequencing technologies. Alternatively, MS (mass spectrometry) could be another option for characterizing modification (taggant) patterns, although it is more complex, time-consuming and expensive than nanopore sequencing.

[0043] According to a further embodiment, the digital data includes a timestamp indicating a specific time relating to the digital data, in particular relating to a creation of the digital data, and / or a time of addition of the timestamp to the digital data.

[0044] The timestamp refers to a specific time that corresponds to or is later than the time of creation of the digital data, thereby providing a proof about the existence of the digital data at the specific time. This is useful to prove a copyright time of the digital data, for example.

[0045] According to a further embodiment, the digital data is provided in a cryptographically secured manner using a cryptographic signature, a cryptographic timestamp, a cryptographic hash, a cryptographic key, a blockchain, a distributed ledger, and / or a cryptographic encryption.

[0046] The digital data (and in particular the object information or the representation of the object information) is provided in a cryptographically secured manner to (i) guarantee the integrity and the origin of the digital data and / or (ii) to protect the digital data from being read by someone who is not entitled to do so. The different available options for cryptographically securing the digital data provide different of the advantages (i) and (ii) and are detailed in the following.

[0047] A cryptographic signature, for instance based upon asymmetric cryptography, provides a proof that the digital data was signed by an allowed issuer (who is in the possession of the private key). The obtained signature can be validated using the corresponding public key, thereby providing the proof that the digital data has been well signed by the allowed issuer and that it was not altered after signature.

[0048] The cryptographic timestamp allows recording a date and time of the digital data, and thereby forms an assertion that the digital data existed at or before a particular time.

[0049] The cryptographic hash (such as a SHA-2 or SHA-3 hash) is yet another solution for ensuring the integrity of the digital data, as modifying the digital data would result in different hash.

[0050] Any other cryptographic key or cryptographic scheme can be used which allows to prove that the digital data has been issued by a legitimate issuer and that the digital data has not been altered after issuance.

[0051] Alternatively, blockchain and / or distributed ledgers can be used to cryptographically secure the digital data. A blockchain may be used to secure a blockchain-based token such as non-fungible token (NFT).

[0052] Cryptographic encryption, using for instance symmetric or asymmetric cryptography, can be used to protect the digital data from illegitimate reader. Asymmetric cryptography can further provide a proof that the digital data was signed by an allowed issuer (who is in possession of the private key).

[0053] Any combination of the above cryptographic solutions can be used to achieve the desired security level for the digital data. Overall, the proposed cryptographic solutions allow providing the tagged digital data-encoding nucleic acid with an unforgeable proof of origin.

[0054] It is further possible to add an error correction code (such as a Reed Solomon code) to the digital data, allowing to account for and correct errors that could arise during the synthesis and sequencing of the nucleic acid.

[0055] According to a second aspect, an object having the tagged digital data-encoding nucleic acid according to the first aspect or an embodiment thereof attached and / or associated thereto is provided.

[0056] All features described in view of the first aspect or any embodiment thereof also hold for the object of the second aspect.

[0057] According to a third aspect, a method for producing a tagged digital data-encoding nucleic acid according to the first aspect or any embodiment thereof is provided. The method comprises:

[0058] (S1) providing digital data;

[0059] (S2) encoding the digital data in at least one data-encoding nucleic acid; and

[0060] (S3) adding a taggant to selected nucleotides of the data-encoding nucleic acid; wherein

[0061] the taggant added to the selected nucleotides is detectable using a detection unit.

[0062] All features described in view of the first aspect or any embodiment thereof also hold for the method of the third aspect and vice versa.

[0063] Step (S3) can be performed after step (S2). In this case, the taggant is added to the already assembled chain of nucleotides forming the data-encoding nucleic acid encoding the digital data. This is for example the case when the tagging is performeda posterioriwith the addition of methyl groups to the data-encoding nucleic acid.

[0064] Alternatively, step (S2) can be performed after step (S3). In this case, the taggant is addeda prioriandin vitroby modifying the nucleotides before they are fully linked to form the data-encoding nucleic acid.

[0065] The step of providing digital data (step S1) can include retrieving the digital data from a storage, receiving and / or opening a file containing the digital data and / or creating the digital data.

[0066] According to an embodiment, the method of the third aspect further comprises:

[0067] associating the tagged digital data-encoding nucleic acid to an object such that the tagged digital data-encoding nucleic acid forms a security marking associated with the object for authenticating the object, wherein the digital data includes an object information describing the object and / or a representation of the object information.

[0068] According to another embodiment, in order to encode the digital data in the at least one data-encoding nucleic acid, the method comprises:

[0069] providing the digital data as a sequence of bits;

[0070] converting the digital data into a virtual sequence of nucleotides by applying an encoding scheme which indicates a correspondence between a specific bit value and / or a specific sequence of bits with a specific nucleotide and / or a specific nucleotide sequence; and

[0071] constructing the at least one digital data-encoding nucleic acid with a sequence of nucleotides corresponding to the virtual sequence of nucleotides.

[0072] In particular, the digital data being provided as a sequence of bits means that the digital data is provided as a series of zeros and ones. This sequence of bits is converted into a virtual sequence of nucleotides, for example into a sequence of virtual A (adenine), C (cytosine), G (guanine) and T (thymine) nucleotides in case of DNA. “Virtual” here means that the virtual sequence can be provided in a digital file, i.e. it represents a sequence of nucleotides that is not (yet) actually existing. The encoding scheme provides a mapping between one or several adjacent bits and corresponding one or several adjacent nucleotides. An example of an encoding scheme is described in the patent application WO2023 / 223068A1, in which a bit at an even position in the sequence of bits is converted to a first nucleotide N1 if said bit has the value 0, and to a second distinct nucleotide N2 if said bit has the value 1, and in which a bit at an odd position in the sequence of bits is converted to a third nucleotide N3 if said bit has the value 0, and to a fourth distinct nucleotide N4 if said bit has the value 1, wherein N1, N2, N3 and N4 are distinct nucleotide bases.

[0073] The virtual sequence of nucleotides is then used as a map to construct the digital data-encoding nucleic acid. This construction can be achieved by means of any known method for synthesizing a nucleic acid. An example for such a synthesis is described in the patent application WO2023 / 223068A1, in which bioblocks of several nucleotides are linked to one another to form a nucleic acid chain. Other syntheses methods in which individual nucleotides are linked to form a nucleic acid chain are also suitable.

[0074] According to another embodiment, the step of encoding the digital data in the at least one data-encoding nucleic acid further comprises:

[0075] inserting at least one virtual non-data sequence of nucleotides before, after and / or between portions of the virtual sequence of nucleotides (also referred to as a fusion sequence), thereby generating a virtual global sequence of nucleotides;

[0076] constructing the virtual global sequence of nucleotides to obtain the at least one digital data-encoding nucleic acid with the sequence of nucleotides corresponding to the virtual global sequence of nucleotides.

[0077] The virtual non-data sequence of nucleotides are nucleotides that do not encode the digital data. Instead, they might encode any other type of information, but they preferably encode position information indicating a position of the virtual non-data sequences of nucleotides amongst the virtual sequence of nucleotides. Such position information can facilitate the decoding and reading of the constructed digital data-encoding nucleic acid, in particular in case of a long digital data-encoding nucleic acid. Preferably, there are several virtual non-data sequences of nucleotides spread (regularly or not) within the virtual sequence of nucleotides.

[0078] The virtual global sequence of nucleotides, including the virtual non-data sequence of nucleotides and the virtual sequence of nucleotides, can be constructed to obtain the digital data-encoding nucleic acid, using the processes described above.

[0079] According to another embodiment, the method further comprises:

[0080] determining an expected taggant pattern on the at least one virtual non-data sequence of nucleotides;

[0081] defining a cryptographic key based on the expected taggant pattern;

[0082] encrypting a predecessor digital data using the cryptographic key, thereby forming the digital data which is encrypted.

[0083] Preferably, the method step described in this embodiment are performed before converting the digital data into a virtual sequence and before constructing the at least one digital data-encoding nucleic acid. The expected taggant pattern corresponds to a pattern that one expects to observe when tagging the virtual non-data sequences of nucleotides using the same taggant than for tagging the entire digital data-encoding nucleic acid. This expected taggant pattern can be determined virtually because the sequence of the virtual non-data sequence of nucleotides is known, i.e. before actually tagging the virtual non-data sequence of nucleotides. The expected taggant pattern can be used to define a corresponding cryptographic key, for example by translating the expected taggant pattern into a sequence of bits, where each nucleotide that is expected to get tagged is expressed as a “1” and each nucleotide that is expected not to get tagged is expressed as a “0”. A predecessor digital data (which is a sequence of bits) can be accordingly encrypted based on this cryptographic key, thereby forming the (encrypted) digital data. The cryptographic key can be unique in case of uniquely provided virtual non-data sequence of nucleotides, or it can be shared by several digital data-encoding nucleic acids. Determining the cryptographic key based on the expected taggant pattern of the virtual non-data sequence of nucleotides is advantageous in that it provides an extra level of protection of the digital data which is accordingly encrypted. In case of a symmetric cryptographic key, when reading the tagged digital data-encoding nucleic acid, the key for decrypting the digital data can be retrieved by determining the taggant pattern in the non-data sequence of nucleotides, thereby allowing to decrypt the digital data. This is advantageous in that no encryption key needs to be stored outside of the digital data-encoding nucleic acid itself.

[0084] According to another embodiment, the step of attaching the taggant to selected nucleotides includes:

[0085] transforming a bacterium expressing at least one gene coding for at least one methyltransferase, wherein the data-encoding nucleic acid is methylated on specific nucleotides recognized and specifically methylated by the at least one methyltransferase; or

[0086] attaching the taggant to the selected nucleotidesin vitroby incubating the data-encoding nucleic acid with at least one purified methyltransferase.

[0087] The bacteria expressing at least one gene coding for at least one methyltransferase can be created specifically for this purpose (proprietary bacterial strains). By adding the digital data-encoding nucleic acid to the bacteria, the bacteria, as it duplicates, adds methylations as a taggant to the digital data-encoding nucleic acid by methyltransferase. The taggant is added to the already assembled chain of nucleotides forming the digital data-encoding nucleic acid encoding the digital data using the bacteria strain. The bacteria additionally allow replication of the digital data-encoding nucleic acid provided therein, thereby allowing amplification of the digital data-encoding nucleic acid.

[0088] The bacteria expressing one or several specific genes coding for methyltransferase(s) can be used for a specific time period, after which new bacteria with different methyltransferase(s) are created and used. The methylation pattern (taggant pattern) is accordingly specific to a certain time period, which allows assigning a time stamp to the tagged digital data-encoding nucleic acid. The ever-changing methyltransferases add an extra layer of protection to the digital data-encoding nucleic acid. Any tagged digital data-encoding nucleic acid displaying a methylation pattern that deviates from this designated period, or exhibiting an incomplete pattern of methylation or a complete absence of methylation, would be identified as copies or counterfeits.

[0089] In bacteria, the Restriction-Modification systems (“R-M” systems) constitute DNA methyltransferases (MTases) and associated restriction enzymes (REases). The R-M systems function like an immune response, protecting bacterial DNA while degrading foreign DNA. Host DNA is methylated by a DNA methyltransferase which protects against digestion from the cognate restriction endonuclease, whereas foreign DNA, such as invading phage DNA, is unmethylated and degraded by the endonuclease. Such “R-M” systems can be harnessed for biotechnological purposes to prevent the replication of the digital data-encoding nucleic acid molecules by a third party. This mechanism involves the association, in the same plasmid, of a gene encoding an endonuclease with the digital data-encoding nucleic acid molecules. The plasmid harboring both the digital data-encoding nucleic acid and the endonuclease encoding sequence is similar to a Trojan horse. Consequently, these nucleic acid molecules can only be replicated and amplified exclusively within the bacterial strain that expresses the correct methyltransferase, thereby preventing the death of the bacterial host cell.

[0090] Alternatively, attaching the taggant to the selected nucleotidesin vitrocorresponds to incubating the digital data-encoding nucleic acid molecules with purified recombinant methyltransferase(s) and S-adenosyl-L-methionine (SAM) as a common methyl group donor, according to standardin vitromethylationprocedures.

[0091] According to a fourth aspect, a method for authenticating the object according to the second aspect or any embodiment thereof is provided. Said method includes:

[0092] detecting the taggant attached to the selected nucleotides to obtain a detected taggant pattern;

[0093] comparing the detected taggant pattern with a predicted taggant pattern and / or a prestored taggant pattern to obtain a taggant pattern similarity degree;

[0094] sequencing the tagged digital data-encoding nucleic acid and optionally decrypting the sequenced information using a cryptographic key obtained with the detected taggant pattern to obtain a decoded information;

[0095] comparing the decoded information with object characteristics, with a prestored authentic object information and / or with a prestored authentic representation of the object information to obtain an information similarity degree; and

[0096] determining whether the object is authentic based on the information similarity degree and / or whether the tagged digital data-encoding nucleic acid is authentic based on the taggant pattern similarity degree.

[0097] All features described in view of the second aspect or any embodiment thereof also hold for the authentication method of the fourth aspect.

[0098] The detection of the methylation taggant to determine the taggant pattern can be performed based on one of the following techniques:

[0099] (i) by performing a sodium bisulfite treatment for the detection of 5mC (5-Methylcytosine): The method involves the bisulfite-catalyzed chemoselective deamination of cytosine resulting in a cytosine to uracil (C -> U) transition, while leaving 5mC largely unaffected by the process (U are further converted in T by PCR (Polymerase Chain Reaction)). Thus, comparative sequencing analysis against a no-reaction control can be used to readily identify the locations of 5mC within a nucleic acid sequence.

[0100] (ii) by performing a sodium nitrite treatment for the detection of 6mA (N6-Methyladenine). The method involves the nitrite-catalyzed hydrolysis of adenine to hypoxanthine (recognized as a guanine by polymerases, A -> G transition), while leaving 6mA unaffected by the process. Thus, comparative sequencing analysis against a no-reaction control can be used to readily identify the locations of 6mA within a nucleic acid sequence.

[0101] The bisulfite-based method (i) is based on a chemical treatment of the methylated nucleic acid to convert certain methylated bases to other natural bases. The detection of methylated bases requires comparison of the nucleotide sequence before and after bisulfite treatment. This contrasts with nanopore sequencing which allows for detection of methylated bases without the need to compare the nucleotide sequence with or without the chemical treatment, as nanopore sequencing allows a direct reading of bases and can distinguish between methylated and non-methylated bases based on subtle differences in the electric signal generated by the passage of the nucleic acid through the nanopore.

[0102] The taggant pattern can be indicative of locations of the nucleotides of the tagged digital data-encoding nucleic acid which are tagged. The detected taggant pattern is the taggant pattern as detected from the tagged digital data-encoding nucleic acid, while the predicted taggant pattern is an expected taggant pattern given the sequence of nucleotides in the tagged digital data-encoding nucleic acid, and the prestored taggant pattern is an expected taggant pattern that was previously stored for comparison purposes, for example when creating the tagged digital data-encoding nucleic acid. The predicted and / or prestored taggant pattern may be stored in a secured manner in the digital data which is then encoded in the digital data-encoding nucleic acid. The taggant pattern similarity degree can be a percentage or ratio of nucleotides of the detected taggant pattern which are identical with the predicted and / or prestored taggant pattern.

[0103] The sequencing of the tagged digital data-encoding nucleic acid allows obtaining the information included therein, in particular the digital data, which can be the object information and / or representation of the object information. Optionally, if the digital data is cryptographically secured in the tagged digital data-encoding nucleic acid, the digital data is decoded to become readable and / or useable.

[0104] Any known method for sequencing the tagged digital data-encoding nucleic acid can be used. For example, it is possible to use a nucleic acid sequencer, preferably a portable one, for the sequencing.

[0105] Once the digital data is retrieved and optionally decoded, the content of the decoded information is compared with object characteristics (in particular visual or easily analyzable characteristics of the object) or with a prestored authentic object information or representation of the object information. The information similarity degree can be an indicator of how similar the decoded information is with the object characteristics, the prestored authentic object information and / or the prestored representation of the object information.

[0106] Both the taggant pattern similarity degree and the information similarity degree are considered to determine whether the object and / or the tagged digital data-encoding nucleic acid are authentic. For example, thresholds for the taggant pattern similarity degree and the information similarity degree below which the object and / or the tagged digital data-encoding nucleic acid are not considered as authentic can be considered.

[0107] The present invention will be described more fully hereinafter with reference to the accompanying figures in which like numerals represent like element throughout the different figures, and in which prominent aspects and features of the invention are illustrated.BRIEF DESCRIPTION OF THE FIGURES

[0108] shows a method for producing a tagged digital data-encoding nucleic acid;

[0109] -ashows an object having the tagged digital data-encoding nucleic acid attached on a surface thereof;

[0110] -bshows an object having the tagged digital data-encoding nucleic acid provided therein;

[0111] shows an object having the tagged digital data-encoding nucleic acid associated thereto;

[0112] shows an example of a certificate;

[0113] shows an example of a processing of text data into tagged digital data-encoding nucleic acid;

[0114] -ashows an example of a creation of a cryptographic key using a taggant pattern of non-data sequences of nucleotides;

[0115] -bshows an example of a construction of a virtual nucleic acid including digital data and non-data;

[0116] shows an example of a bacterium methylating a digital data-encoding nucleic acid; and

[0117] shows a method for authenticating an object.DETAILED DESCRIPTION

[0118] shows an example for a method for producing a tagged digital data-encoding nucleic acid 1. The method comprises steps S1 to S3. In step S1, digital data 4 is provided. The digital data 4 is here provided as a sequence of bits 18. The “….” in the sequence of bits 18 shown inindicate that only part of the sequence is shown. Here, the digital data 4 is provided for instance as a digital file and includes an identification information of a product (object).

[0119] In step S1’ of, the digital data 4 is encoded in at least one virtual digital data-encoding nucleic acid 8, here DNA. The step S1’ usually includes the step of virtually converting the digital data 4 into a virtual sequence of nucleotides 16 by applying an encoding scheme indicating a correspondence between each bit 18 and a specific nucleotide 16. In the example of, the bits 18 of the digital data 4 “100111001101001....100100110010001” are converted into the virtual sequence of nucleotides 16 “GACTGTCAGTCTCAG....GACTCAGTCAGACAG” (with A standing for adenine, C for cytosine, G for guanine and T for thymine).

[0120] In step S2 of, a digital data-encoding nucleic acid 2 is constructed by assembling nucleotides 15 based upon the virtual digital data-encoding nucleic acid 8. The digital data-encoding nucleic acid 2 is hence a real (not digital) sequence of nucleotides 15 respectively corresponding to the virtual nucleotides 16.

[0121] In step S3 of, a taggant 3 is attached to selected nucleotides 15, thereby constructing the tagged digital data-encoding nucleic acid 1. The selected nucleotides 15 to which the taggant 3 is attached is indicated by a framed nucleotide 15 inHere, the taggant 3 is a methylation of specific nucleotides 15. The process for such a methylation is described further below.

[0122] The methylation is achieved using specifically designed bacteria. Without those specifically designed bacteria, which are very hard to reproduce without having access to the original bacteria, it is almost impossible to copy the tagged digital data-encoding nucleic acid 1. The taggant 3 hence provides for an anti-copy, rendering the tagged digital data-encoding nucleic acid 1 more secure and reliable.

[0123] The method ofallows storing any type of digital data 4 in the tagged digital data-encoding nucleic acid 1. When the digital data 4 includes an identification information of an object 5 or another information relating to such an object 5 (object information), the tagged digital data-encoding nucleic acid 1 is advantageously attached or associated with such an object 5, as shown in-a,-b and, respectively. Namely, the tagged digital data-encoding nucleic acid 1 is embedded in a marking, which thereby becomes a security marking 6. The security marking 6 is either attached to the object 5 (-a), attached (embedded) inside the object 5 (-b) or provided separately from the object 5 but in association therewith () for authentication purposes. To provide the tagged digital data-encoding nucleic acid 1 in the security marking 6, the tagged digital data-encoding nucleic acid 1 can be encapsulated in a substrate.

[0124] In order to secure the tagged digital data-encoding nucleic acid 1 even further, it is possible to cryptographically secure the digital data 4 itself. Examples for securing the digital data 4 are described below in view ofand 5.

[0125] and 5 describe an example in which the digital data 4 is created from a document, which is a certificate 7 associated to an object 5 for authentication purposes. As shown in, the certificate 7 includes a certificate content 9. The certificate 7 is issued by a legitimate issuer, for instance a certification authority and contains, in the certificate content 9, an identification information (a serial number) of the object 5, a description of the object 5 (its size, color, shape, fingerprint or the like), the provenance of the object 5, the production date of the object 5, the name of the certifier authority, a GPS coordinate of the object 5, or the like. The certificate content 9 is cryptographically secured, in the present example by a cryptographic signature 12.

[0126] The content of the cryptographic signature 12 described above can be encoded in a tagged digital data-encoding nucleic acid 1, thereby making it even harder to falsify or duplicate. The process for encoding the cryptographic signature 12 in the tagged digital data-encoding nucleic acid 1 is shown as part of the processing of text data into digital data illustrated in

[0127] As shown in, the encoding process starts with the text 10 forming the certificate content 9 in step S4. It is indicated that the content of text 10 is illustrative only and that an alternative text, including in an alternative language and / or data under any digital format (binary for instance), could also be provided. In step S5, the text 10 is converted into a sequence 11 of bits 18. In a step S6, the cryptographic signature 12 is added as a sequence of bits 18 (for instance) to the end of the sequence 11. Between step S6 and S7, the dataset of step S6 can be cryptographically encrypted using a symmetric cryptographic key 26, thereby obtaining an encrypted sequence 13 in step S7. In step S8, an error correction code 14 is added to the encrypted sequence 13 of step S7 in order to compensate for some synthesis or sequencing errors. In step S9, the dataset of step S8 is converted into a sequence of (real, non-virtual) nucleotides 15, which is then constructed and tagged with taggants 3 (along the same lines as in step S3 described above).

[0128] In the process of, steps S4 to S8 correspond to step S1 of, with the dataset in step S8 corresponding to the digital data 4 and forming an encrypted representation of the object information. Step S9 ofcorresponds to steps S1’, S2 and S3 of

[0129] -a shows a method for obtaining the symmetric cryptographic key 26 used to go from step S6 to step S7 ofIn the example of-a, the symmetric cryptographic key 26 is determined from an expected methylation pattern of virtual non-data sequences of nucleotides 17, as explained in the following.

[0130] Namely, the virtual non-data sequences of nucleotides 17 are a virtual representation of non-data sequences of nucleotides which are predefined, and for example form standard building blocks of nucleotides. The virtual non-data sequences of nucleotides 17 are meant to be inserted into the virtual digital data-encoding nucleic acid 8 to indicate position information. Accordingly, the non-data sequences of nucleotides (corresponding to the virtual non-data sequences of nucleotides 17) are provided within the digital data-encoding nucleic acid 2 to indicate position information, i.e. positions useful for sequencing the nucleic acid 1 once it has accordingly been constructed.

[0131] As shown in-a, in a step S20, the virtual non-data sequences of nucleotides 17 are considered. The virtual non-data sequences of nucleotides 17 being known, they also have known methylation sites corresponding to the used methylation bacterium, said methylation sites being framed in-a. In a step S21 of-a, the virtual non-data sequences of nucleotides 17 are respectively converted into corresponding virtual non-data sequences of bits 30, 31, in which a “1” indicates tagged (i.e. methylated) nucleotides and a “0” indicates non-tagged (i.e. non-methylated) nucleotides. In a step S22, the virtual non-data sequences of bits 30, 31 are assembled to form the symmetric cryptographic key 26 used to go from step S6 to step S7 of

[0132] -b shows a virtual representation of the nucleic acid 1, which is constructed such as to include the digital data 4 and the virtual non-data sequence of nucleotides 17 described in-a. Namely, the virtual non-data sequence of nucleotides 17 of-a can be inserted as virtual non-data sequence of nucleotides 17a, 17b between blocks 4a, 4b, 4c of the digital data 4, thereby providing labels regarding the position of the blocks of digital data 4. In detail, the virtual nucleic acid can include a block 4a of the digital data 4, a subsequent virtual non-data sequence of nucleotides 17a, another subsequent block 4b of the digital data 4, another subsequent virtual non-data sequence of nucleotides 17b, another subsequent block 4c of the digital data 4, and so on. The virtual non-data sequence of nucleotides 17a, 17b correspond to previously described virtual non-data sequences of nucleotides 17, wherein the “a” and “b” in 17a, 17b are to distinguish between the two virtual non-data sequence of nucleotides 17. The (real, non-virtual) nucleic acid 1 can be constructed based on the virtual nucleic acid shown in-b. The symmetric cryptographic key 26 can be retrieved from the tagged digital data-encoding nucleic acid 1 during sequencing thereof, and used to decode the digital data 4. At the same time, the taggant 3 still serves as an anti-copy in the tagged digital data-encoding nucleic acid 1, as is also the case in the processes described inand 5.

[0133] shows an example of how the taggant 3 can be attached to the selected nucleotides 15 through methylation in step S3 ofand step S9 ofTo achieve such a methylation, a bacterium 20 with the suitable genotype is selected and the bacterial chromosome 21 is modified by inserting at least one methyltransferase encoding sequence 23 into the bacterial chromosome 21 between the insertion positions 22 (-a). As a result, upon duplication of the bacterium 20, and expression of the methyltransferase encoding sequence(s) 23, the bacterial chromosome 21 is methylated at specific nucleotides to constitute methylation sites / patterns 24 (-b). Then, when a plasmid 25 containing the digital data-encoding nucleic acid 2 is introduced into the bacterium 20 (-c), a similar methylation pattern governed by the methyltransferase encoding sequence(s) 23 inserted into the bacterial chromosome 21 is reproduced on the plasmid 25 at the level of the data sequences and the non-data sequences (-d), thereby achieving methylation on the selected nucleotides 15 (represented by the taggant 3 in-d) and creating the tagged digital data-encoding nucleic acid 1.

[0134] describes a method for authenticating the object 5 to which the security marking 6 with the tagged digital data-encoding nucleic acid 1 is associated. The method ofcomprises steps S10 to S14. In step S10, the taggant 3 attached to the selected nucleotides 15 is detected to obtain a detected taggant pattern DTP indicative of which nucleotides 15 are tagged and which ones are not. In a step S11, a predicted and / or prestored taggant pattern PTP, which is a taggant pattern expected for this tagged digital data-encoding nucleic acid 1, is retrieved and compared to the detected taggant pattern DTP. A similarity score between the detected taggant pattern DTP and the predicted or prestored taggant pattern is determined as a taggant pattern similarity degree TPSD.

[0135] In step S12, the tagged digital data-encoding nucleic acid 1 is sequenced and optionally decrypted to obtain a decoded information DI, which corresponds to the digital data 4. In step S13, the decoded information DI is compared with an expected information (object characteristics OC, prestored authentic information PAI including a prestored authentic object information and / or prestored authentic representation of the object information), for example the available content of the certificate 7. The result of the comparison of step S13 is an information similarity degree ISD. In step S14, it is determined whether the object 5 is authentic based on the information similarity degree ISD and whether the security marking 6 is authentic based on the taggant pattern similarity degree TPSD.

[0136] Optionally, in step S12, the cryptographic key for decrypting the sequenced data is determined based on the detected taggant pattern for the portions corresponding to the virtual non-data sequence of nucleotides 17, as described in view of-a and 6-b. In the case of methylation, steps S11 and S12 can be performed concurrently.

[0137] The above disclosed subject-matter is to be considered illustrative, and not restrictive, and serves to provide a better understanding of the invention defined by the independent claims.Preferred embodiments of the invention

[0138] 1. A tagged digital data-encoding nucleic acid (1) comprising:

[0139] (a) at least one digital data-encoding nucleic acid (2) encoding digital data (4); and

[0140] (b) at least one taggant (3) that is attached to selected nucleotides (15), wherein the taggant (3) attached to the selected nucleotides (15) is detectable using a detection unit.

[0141] 2. The tagged digital data-encoding nucleic acid according to embodiment 1 configured to form a security marking (6) associated with an object (5) for authenticating the object (5), wherein:

[0142] the digital data (4) includes an object information describing the object (5) and / or a representation of the object information.

[0143] 3. The tagged digital data-encoding nucleic acid according to embodiment 1 and 2, wherein the taggant (3) includes:

[0144] a chemical marker chemically modifying the selected nucleotides (15); and / or

[0145] an isotopic marker.

[0146] 4. The tagged digital data-encoding nucleic acid according to embodiment 3, wherein the chemical modification includes: methylation, hydroxymethylation, formylation, carboxylation, glycosylation, alkylation, phosphorylation, base excision, base chemical modification, colorimetric marking and / or fluorescent marking.

[0147] 5. The tagged digital data-encoding nucleic acid according to any one of embodiments 1 to 4, wherein the digital data (4) includes a timestamp indicating a specific time relating to the digital data (4), in particular relating to a creation of the digital data (4), and / or a time of addition of the timestamp to the digital data (4).

[0148] 6. The tagged digital data-encoding nucleic acid according to any one of embodiments 1 to 5, wherein the digital data (4) is provided in a cryptographically secured manner using a cryptographic signature, a cryptographic timestamp, a cryptographic hash, a cryptographic key, a blockchain, a distributed ledger, and / or a cryptographic encryption.

[0149] 7. An object (5) having the tagged digital data-encoding nucleic acid (1) according to any one of embodiments 1 to 6 attached and / or associated thereto.

[0150] 8. A method for producing a tagged digital data-encoding nucleic acid (1) according to any one of embodiments 1 to 6, the method comprising:

[0151] (S1) providing digital data (4);

[0152] (S2) encoding the digital data (4) in at least one digital data-encoding nucleic acid (2); and

[0153] (S3) adding a taggant (3) to selected nucleotides (15) of the digital data-encoding nucleic acid (2); wherein

[0154] the taggant (3) added to the selected nucleotides (15) is detectable using a detection unit.

[0155] 9. The method according to embodiment 8, further comprising:

[0156] associating the tagged digital data-encoding nucleic acid (1) to an object (5) such that the tagged digital data-encoding nucleic acid (1) forms a security marking (6) associated with the object (5) for authenticating the object (5), wherein the digital data (4) includes an object information describing the object (5) and / or a representation of the object information.

[0157] 10. The method according to embodiment 8 or 9, wherein in order to encode (S2) the digital data (4) in the at least one digital data-encoding nucleic acid (2), the method comprises:

[0158] providing the digital data (4) as a sequence of bits (18);

[0159] converting (S1’) the digital data (4) into a virtual sequence of nucleotides (16) by applying an encoding scheme which indicates a correspondence between a specific bit value and / or a specific sequence of bits with a specific nucleotide and / or a specific nucleotide sequence; and

[0160] constructing the at least one digital data-encoding nucleic acid (2) with a sequence of nucleotides (15) corresponding to the virtual sequence of nucleotides (16).

[0161] 11. The method according to embodiment 10, wherein the step of encoding (S2) the digital data (4) in the at least one digital data-encoding nucleic acid (2) further comprises:

[0162] inserting at least one virtual non-data sequence (17) of nucleotides before, after and / or between portions of the virtual sequence of nucleotides (16), thereby generating a virtual global sequence of nucleotides;

[0163] constructing the virtual global sequence of nucleotides to obtain the at least one digital data-encoding nucleic acid (2) with the sequence of nucleotides corresponding to the virtual global sequence of nucleotides.

[0164] 12. The method according to embodiment 11, further comprising:

[0165] determining an expected taggant pattern on the at least one virtual non-data sequence (17) of nucleotides;

[0166] defining a cryptographic key (26) based on the expected taggant pattern;

[0167] encrypting a predecessor digital data using the cryptographic key (26) , thereby forming the digital data (4) which is encrypted.

[0168] 13. The method according to any one of embodiments 8 to 12, wherein the step of attaching the taggant (3) to selected nucleotides (15) includes:

[0169] transforming a bacterium expressing at least one gene coding for at least one methyltransferase, wherein the data-encoding nucleic acid is methylated on specific nucleotides (15) recognized and specifically methylated by the at least one methyltransferase; or

[0170] attaching the taggant (3) to the selected nucleotides (15)in vitroby incubating the data-encoding nucleic acid with at least one purified methyltransferase.

[0171] 14. A method for authenticating the object (5) according to embodiment 7, the method including:

[0172] detecting (S10) the taggant (3) attached to the selected nucleotides (15) to obtain a detected taggant pattern;

[0173] comparing (S11) the detected taggant pattern with a predicted taggant pattern and / or a prestored taggant pattern to obtain a taggant pattern similarity degree;

[0174] sequencing (S12) the tagged digital data-encoding nucleic acid (1) and optionally decrypting the sequenced information using a cryptographic key obtained with the detected taggant pattern to obtain a decoded information;

[0175] comparing (S13) the decoded information with object characteristics, with a prestored authentic object information and / or with a prestored authentic representation of the object information to obtain an information similarity degree; and

[0176] determining (S14) whether the object (5) is authentic based on the information similarity degree and / or whether the tagged digital data-encoding nucleic acid (1) is authentic based on the taggant pattern similarity degree.REFERENCE NUMERALS

[0177] 1 tagged digital data-encoding nucleic acid

[0178] 2 digital data-encoding nucleic acid

[0179] 3 taggant

[0180] 4 digital data

[0181] 4a, 4b, 4c digital data block

[0182] 5 object

[0183] 6 security marking

[0184] 7 certificate

[0185] 8 virtual digital data-encoding nucleic acid

[0186] 9 certificate content

[0187] 10 text or data

[0188] 11 sequence of bits

[0189] 12 cryptographic signature

[0190] 13 encrypted sequence

[0191] 14 error correction code

[0192] 15 nucleotide

[0193] 16 virtual nucleotide

[0194] 17, 17a, 17b virtual non-data sequence of nucleotides

[0195] 18 bit

[0196] 20 bacterium

[0197] 21 bacterial chromosome

[0198] 22 insertion position

[0199] 23 methyltransferase encoding sequence

[0200] 24 methylation site

[0201] 25 plasmid

[0202] 26 symmetric cryptographic key

[0203] 30 virtual non-data sequence of bits

[0204] 31 virtual non-data sequence of bits

Claims

A tagged digital data-encoding nucleic acid (1) comprising:(a) at least one digital data-encoding nucleic acid (2) encoding digital data (4); and(b) at least one taggant (3) that is attached to selected nucleotides (15), wherein the taggant (3) attached to the selected nucleotides (15) is detectable using a detection unit.The tagged digital data-encoding nucleic acid according to claim 1, wherein the taggant includes a chemical marker chemically modifying the selected nucleotides, wherein the chemically modifying is methylation.A tagged digital data-encoding deoxyribonucleic acid (1) (DNA) according to claim 1 or 2, comprising:at least one digital data-encoding DNA (2) encoding digital data (4), wherein the digital data-encoding DNA comprises:a strand comprisingmDNA service blocks ofnnucleotides, wherein at least 2 of the DNA service blocks independently encode digital data, andmis from 2 to 250, andnis from 4 to 200;each DNA service block being linked to its following DNA service block by a fusion sequence, the fusion sequence consisting of at least three nucleotides, which fusion sequence is invariant, and the fusion sequence is absent from the DNA service blocks; andat least one DNA service block bears at least one taggant which is a methylated nucleotide, at a DNA methyl transferase recognition site.The tagged digital data-encoding DNA according to claim 3, whereinnis 2-100, preferably 2-80, more preferably 2-50, more particularly preferably 2-10, alternativelynis 2-4, particularly 4.The tagged digital data-encoding DNA according to claim 3 or 4, whereinnis invariant.The tagged digital data-encoding DNA according to claim 3, 4 or 5, wherein the fusion sequence consists of at least 4 nucleotides, preferably 4 to 50 nucleotides, more preferably 4 to 40 nucleotides, more particularly preferably it consists of 4 nucleotides.The tagged digital data-encoding DNA according to any one of claims 3-6, wherein the fusion sequences comprise a stop codon.The tagged digital data-encoding DNA according to any one of claims 3-7, wherein the fusion sequence comprises the sequence TTAG.The tagged digital data-encoding DNA according to any one of claims 3-8, whereinmis from 2 to 250, preferably 2 to 70, more preferably 4 to 30, more particularly preferably 4 to 20.The tagged digital data-encoding nucleic acid according to any one preceding claim, configured to form a security marking (6) associated with an object (5) for authenticating the object (5), wherein:the digital data (4) includes an object information describing the object (5) and / or a representation of the object information.The tagged digital data-encoding nucleic acid according to any one preceding claim, wherein the digital data (4) includes a timestamp indicating a specific time relating to the digital data (4), in particular relating to a creation of the digital data (4), and / or a time of addition of the timestamp to the digital data (4).The tagged digital data-encoding nucleic acid according to any one preceding claim, wherein the digital data (4) is provided in a cryptographically secured manner using a cryptographic signature, a cryptographic timestamp, a cryptographic hash, a cryptographic key, a blockchain, a distributed ledger, and / or a cryptographic encryption.An object (5) having the tagged digital data-encoding nucleic acid (1) according to any one preceding claim attached and / or associated thereto.A method for producing a tagged digital data-encoding nucleic acid (1) according to any one of claims 1 to 12, the method comprising:(S1) providing digital data (4);(S2) encoding the digital data (4) in at least one digital data-encoding nucleic acid (2); and(S3) adding a taggant (3) to selected nucleotides (15) of the digital data-encoding nucleic acid (2); whereinthe taggant (3) added to the selected nucleotides (15) is detectable using a detection unit.The method according to claim 14, further comprising:associating the tagged digital data-encoding nucleic acid (1) to an object (5) such that the tagged digital data-encoding nucleic acid (1) forms a security marking (6) associated with the object (5) for authenticating the object (5), wherein the digital data (4) includes an object information describing the object (5) and / or a representation of the object information.The method according to claim 14 or 15, wherein in order to encode (S2) the digital data (4) in the at least one digital data-encoding nucleic acid (2), the method comprises:providing the digital data (4) as a sequence of bits (18);converting (S1’) the digital data (4) into a virtual sequence of nucleotides (16) by applying an encoding scheme which indicates a correspondence between a specific bit value and / or a specific sequence of bits with a specific nucleotide and / or a specific nucleotide sequence; andconstructing the at least one digital data-encoding nucleic acid (2) with a sequence of nucleotides (15) corresponding to the virtual sequence of nucleotides (16).The method according to claim 16, wherein the step of encoding (S2) the digital data (4) in the at least one digital data-encoding nucleic acid (2) further comprises:inserting at least one virtual non-data sequence (17) of nucleotides before, after and / or between portions of the virtual sequence of nucleotides (16), thereby generating a virtual global sequence of nucleotides;constructing the virtual global sequence of nucleotides to obtain the at least one digital data-encoding nucleic acid (2) with the sequence of nucleotides corresponding to the virtual global sequence of nucleotides.The method according to claim 17, further comprising:determining an expected taggant pattern on the at least one virtual non-data sequence (17) of nucleotides;defining a cryptographic key (26) based on the expected taggant pattern;encrypting a predecessor digital data using the cryptographic key (26) , thereby forming the digital data (4) which is encrypted.The method according to any one of claims 14 to 18, wherein the step of attaching the taggant (3) to selected nucleotides (15) includes:transforming a bacterium expressing at least one gene coding for at least one methyltransferase, wherein the data-encoding nucleic acid is methylated on specific nucleotides (15) recognized and specifically methylated by the at least one methyltransferase; orattaching the taggant (3) to the selected nucleotides (15)in vitroby incubating the data-encoding nucleic acid with at least one purified methyltransferase.A method for authenticating the object (5) according to claim 13, the method including:detecting (S10) the taggant (3) attached to the selected nucleotides (15) to obtain a detected taggant pattern;comparing (S11) the detected taggant pattern with a predicted taggant pattern and / or a prestored taggant pattern to obtain a taggant pattern similarity degree;sequencing (S12) the tagged digital data-encoding nucleic acid (1) and optionally decrypting the sequenced information using a cryptographic key obtained with the detected taggant pattern to obtain a decoded information;comparing (S13) the decoded information with object characteristics, with a prestored authentic object information and / or with a prestored authentic representation of the object information to obtain an information similarity degree; anddetermining (S14) whether the object (5) is authentic based on the information similarity degree and / or whether the tagged digital data-encoding nucleic acid (1) is authentic based on the taggant pattern similarity degree.

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