Advanced data encryption protection technology for DNA information storage

Abstract

The invention discloses an advanced data encryption protection technology for DNA information storage, and the specific technical scheme of the technology comprises the steps: coding to-be-encrypted data into small information blocks and transcoding the small information blocks into a DNA sequence through a coding and encryption scheme, after the DNA sequence is synthesized, introducing interference information through random errors or fractures, the interference intensity of random combination interference noise is effectively improved; the method for decrypting the DNA library carrying the encrypted information comprises the steps of sequencing, fragment assembly, information small block reconstruction, reordering and decoding, and finally decoding the original information based on an erasure coding scheme. The technology has a wide application prospect in the field of data storage and protection.

Description

Technical Field

[0001] The invention belongs to the field of bioinformatics and synthetic biology and is an advanced data encryption protection technology for DNA information storage. Background Art

[0002] As the demand for data storage continues to grow, traditional electronic storage methods face challenges of capacity limitations and security risks. Therefore, it is particularly important to find new data storage and encryption protection technologies. As an emerging storage technology, DNA information storage has extremely high density and long-term data preservation capabilities, and has become one of the research hotspots. On the other hand, the characteristics of DNA storage give it unique advantages in security and privacy protection. Data encryption technology for DNA storage can be implemented in a variety of ways. The following are existing strategies and methods:

[0003] Hybrid encryption: This method mixes the information to be encrypted with a large number of random DNA sequences. It is like hiding the real information in a pile of information. First, we need to generate enough random DNA sequences, and then encode the information to be encrypted into DNA sequences and mix them with the randomly generated sequences. When decrypting, only those who have the correct password (here may be some kind of mark or identification sequence) can find the real information from these sequences.

[0004] Hiding information: This method hides information in a specific area of ​​DNA that is known to the decryptor but unknown to others. First, we need to encode the information into a DNA sequence and then insert this sequence into a specific position of a larger DNA sequence. During decryption, only those who know this position can extract the encrypted information.

[0005] Molecular encryption: This is to encrypt information by performing specific biochemical reactions on DNA (for example, by DNA cutting or gene editing). First, we need to encode the information into a DNA sequence, and then perform a specific biochemical reaction on this sequence. This reaction will change part of the DNA sequence but not other parts. When decrypting, only those who know this reaction can restore the encrypted information.

[0006] Specific coding strategy: This is to encode information into DNA through a specific coding method. This may involve specific sequence design, specific coding rules, etc. When decrypting, only those who know this coding strategy can interpret the information.

[0007] Sequence permutation: This method is to encrypt information by changing the order of DNA sequence. First, we need to encode the information into a DNA sequence, and then reorder the sequence. When decrypting, only those who know the ordering rules of the original sequence can rearrange the sequence and decrypt the information.

[0008] Introduction of point mutation: Introducing point mutations (changing a single base) at specific positions in the DNA sequence to achieve information encryption. First, we need to encode the information into a DNA sequence, and then introduce point mutations at specific positions in this sequence. When decrypting, only those who know which positions have mutated can restore the encrypted information.

[0009] Multi-chain encryption: Information is distributed across multiple DNA chains to achieve encryption. First, we need to divide the information into multiple parts, and then encode each part as an independent DNA sequence. These sequences can be mixed together or stored separately. When decrypting, all sequences need to be read out and then combined in the correct order to decrypt the complete information.

[0010] Paired chain encryption: Using the complementary pairing principle of DNA, information is encrypted by designing a specific complementary chain. First, we need to encode the information into a DNA sequence, and then design a complementary chain based on this sequence. This complementary chain can be used as both an encrypted password and a part of the information. When decrypting, only those who know this complementary chain can decrypt the information.

[0011] Shape-based encryption (DNA origami encryption): This method uses DNA origami technology to encrypt information by changing the three-dimensional structure of DNA. First, we need to encode the information into a DNA sequence, and then design a specific three-dimensional DNA structure based on this sequence. This structure can be used as an encrypted password or as part of the information. When decrypting, only those who know this three-dimensional structure can decrypt the information.

[0012] Location-based encryption (DNA chip encryption): This method is to place encrypted information at a specific location on the DNA chip. First, we need to encode the information into a DNA sequence, and then place this sequence at a specific location on the DNA chip. This location can be used as an encrypted password or as part of the information. When decrypting, only those who know this location can decrypt the information.

[0013] Sequence-based encryption (DNA hybridization encryption): This method is to encrypt information by designing a specific complementary sequence. First, we need to encode the information into a DNA sequence, and then design a complementary sequence based on this sequence. This complementary sequence can be used as both an encrypted password and a part of the information. When decrypting, only those who know this complementary sequence can decrypt the information.

[0014] Although existing technologies and strategies have their own characteristics and advantages, they also have some obvious shortcomings and limitations. One of the biggest problems is that these strategies fail to fully utilize and give play to the characteristics of DNA as an information storage medium, especially its unique multi-copy characteristics containing random errors. In the entire process of DNA information storage, for each information unit, there are always multiple corresponding copies containing random base errors. Existing encryption strategies are not designed or processed for this characteristic. Some schemes try to use different copies of DNA molecules to form interference and increase the difficulty of the decryption process. However, these schemes can usually only introduce a small number of base differences, which are easily identified by attackers to carry out targeted base difference elimination and cracking attacks. In addition, these strategies lack effective means to deal with random base errors, or ignore the potential of these information copies in enhancing information security and reliability. For example, in the process of storing and reading large-scale data, replication errors may accumulate, resulting in data loss. For example, for strategies such as hybrid encryption, hidden information, specific encoding strategies, sequence substitution, etc., if the random errors generated during DNA replication are not properly handled, the encrypted information may be damaged. Similarly, in shape-based encryption (DNA origami encryption) and position-based encryption (DNA chip encryption), any replication error may cause the encrypted information to become unrecognizable or misunderstood. For strategies such as point mutation introduction and multi-chain encryption, although they can deal with the problem of replication errors to some extent, there are still other problems. For example, in the process of storing and reading large-scale data, replication errors may accumulate, resulting in a large amount of data loss. In addition, for multi-chain encryption strategies, although errors can be detected and corrected by comparing the sequences of different chains, this requires a lot of computing resources and is not guaranteed to be successful in all cases.

[0015] In order to overcome the various limitations of existing DNA-based encryption methods, the technology of the present invention fully exploits the complex multi-molecule copy characteristics of DNA information storage to greatly enhance the protection of encrypted information. The present invention effectively improves the interference intensity of random combination interference noise by introducing random errors and random DNA fragment breakage steps. And through the innovatively designed encryption encoding and decoding system, the impact of a large number of random combination interference noises on encrypted information can be efficiently dealt with. In addition, the present invention adopts the design of block-by-block separate encryption and fountain code encoding scheme, and the failure of decryption of any small block of data will cause the failure of decryption of the entire information, further enhancing the security of encrypted information. For users holding keys, the correct DNA fragments can be quickly and accurately assembled with the assistance of key information, so as to quickly and accurately decrypt data. However, for those who attempt to illegally steal information, due to the lack of the correct key, they need to randomly brute-force crack each similar copy of information. This will waste a lot of cracking computing power on the wrong information copy. Moreover, any small piece of information will fail to decode the entire information due to the incorrect decryption process caused by the use of the wrong information copy, thereby forming a strong protection for the encrypted information. In addition, due to the introduction of the DNA assembly algorithm, the technology of the present invention can efficiently handle the problem of DNA degradation and support the long-term reliability of encrypted storage information.

[0016] In general, the advantages of the invention are reflected in improving data security, greatly increasing the complexity of cracking, and providing long-term data stability. And compared with some DNA encryption methods that rely on complex calculations, the amount of calculation required by this solution is lower, which improves the efficiency of encryption and decryption. These characteristics make the present invention more able to meet the needs of efficient and secure DNA information encryption protection. Summary of the invention

[0017] The present invention aims to provide an advanced data encryption protection technology based on DNA information storage. Through the cleverly designed DNA information storage encryption and decoding system and the introduced interference information enhancement means, the technology of the present invention fully exploits the complex multi-molecule copy characteristics of DNA information storage to greatly enhance the protection of encrypted information. The present invention effectively improves the interference intensity of random combination interference noise by introducing random errors and random DNA fragment breakage steps. And through the innovatively designed encryption and decoding system, it efficiently copes with the impact of a large amount of random combination interference noise on real information. In addition, the technical invention uses the design of block-by-block separate encryption and the fountain code encoding scheme. The failure to decrypt any small block of data will cause the failure of decryption of the entire information, further enhancing the security of encrypted information.

[0018] For users who hold the key, they can quickly and accurately assemble the correct DNA fragment with the help of the key information, so as to quickly and accurately decrypt the data. However, for those who attempt to steal information illegally, due to the lack of the correct key, they need to randomly brute force each similar copy of the information. This will waste a lot of cracking computing power on the wrong copy of the information, thus forming a strong protection barrier for the copy of the encrypted information.

[0019] The present invention specifically provides:

[0020] The first aspect of the present invention provides a method for encrypting DNA storage information, comprising the following steps:

[0021] Step 1, encoding small information blocks: Encode the data to be encrypted into a certain number of small information blocks through erasure coding, each data fragment includes an index and a data carrying area;

[0022] Step 2, encryption: perform encryption operations on the data of each small block of information;

[0023] Step 3, adding ECC checksum and scrambling the byte sequence: adding ECC code to each encrypted information block, and performing pseudo-random scrambling on the byte sequence with the ECC code added;

[0024] Step 4, transcoding the byte sequence of the encrypted and scrambled information block into a DNA sequence;

[0025] Step 5, synthesizing the DNA sequence obtained in step 4 by high-throughput DNA synthesis technology;

[0026] Step 6: random interference information import and combined interference enhancement.

[0027] In a specific embodiment of the present invention, the erasure coding in step 1 is fountain code, Reed-Solomon (RS) code or LDPC code.

[0028] In the preferred embodiment of the present invention, fountain codes are used. If a small number of data fragments are erroneous, the entire information will be lost. The fountain code scheme is more conducive to enhancing the encryption protection strength of the information.

[0029] In a specific embodiment of the present invention, DES, AES (Advanced Encryption Standard), 3DES (Triple Data Encryption Standard) are used as optional encryption schemes in step 2; preferably, DES is used.

[0030] In a specific embodiment of the present invention, CRC32 is used as the ECC encoding scheme of the data segment in step 3.

[0031] In a specific embodiment of the present invention, the index value of the information block and the key of the encryption scheme in step 2 are used as the seed value of the pseudo-random function in step 3, thereby preventing information thieves without the key from successfully performing ECC verification.

[0032] In a specific embodiment of the present invention, the base-bit correspondence relationship used is:

[0033]

[0034]

[0035] Or any other combination among the 24 base bit combination correspondences.

[0036] In a specific embodiment of the present invention, the DNA sequence synthesized in step 5 has a linker.

[0037] In a specific embodiment of the present invention, in step 6, the introduction of interference information and the enhancement of combined interference are achieved through error-prone PCR, or high temperature degradation treatment, or ultraviolet treatment, or DNAase I enzymatic treatment, or a combination of any of the above techniques.

[0038] The second aspect of the present invention provides a DNA library carrying encrypted information obtained by the method of the first aspect of the present invention.

[0039] The third aspect of the present invention provides a method for decrypting the DNA library carrying the encrypted information in the second aspect:

[0040] Step 1, high-throughput sequencing: high-throughput sequencing of the encrypted and stored DNA samples;

[0041] Step 2, DNA fragment assembly and reconstruction;

[0042] Step 3, reconstructing the information block: reconstructing the scrambled and encrypted information block through the base-bit correspondence;

[0043] Step 4, reordering and data ECC verification of the reconstructed information blocks; the ordering method and verification method are based on the ECC check code and pseudo-random scrambling algorithm used in the encryption writing process;

[0044] Step 5, using the key to decode the reordered information blocks;

[0045] Step 6: Decode the original information based on the erasure coding scheme.

[0046] In a specific embodiment of the present invention, step 1 uses an Illumina sequencer for high-throughput sequencing, and the read length of double-end sequencing is 150bp*2, or nanopore sequencing is used.

[0047] In a specific embodiment of the present invention, the base-bit correspondence relationship used in step 3 is:

[0048]

[0049] Or any other combination among the 24 base bit combination correspondences.

[0050] In a specific embodiment of the present invention, the steps 2) to 4) are an assembly method based on the Debret diagram, specifically comprising:

[0051] Step S1, calculating the initial k-mer of the current DNA sequence to be assembled according to the index information;

[0052] Step S2, searching for a k-mer connected to the k-mer in the Debrecen graph (DBG) graph; if not found, the assembly of the current DNA fragment fails;

[0053] Step S3, if connected k-mers are found in the DBG graph, these k-mers are placed at the end of the search path; each k-mer found forms an independent terminal k-mer node;

[0054] Step S4, judging the node, if the path length does not reach the length of the DNA fragment, repeating steps S2-S4 until the path length meets the length of the DNA fragment;

[0055] Step S5, when the path length reaches the length of the DNA sequence, the path is reordered according to the index and key information; this step is a reverse operation introduced in the encoding process to randomly shuffle the path according to the index and key information; after this step, the encrypted information bytes and ECC bytes will be returned to their original positions;

[0056] Step S6, reading the ECC value of the path-related DNA sequence and performing ECC verification;

[0057] Step S7, judging the node, judging the number of paths that meet the ECC check; if the number of paths is zero or greater than 1, the DNA sequence assembly process in this direction fails; if the number of paths is 1, outputting the relevant DNA sequence;

[0058] Step S8: If the number of paths that meet the ECC check is 1, the DNA sequence contained in the path is output.

[0059] After the above steps are completed, the corresponding indexed DNA fragments and encrypted information blocks can be obtained.

[0060] A fourth aspect of the present invention provides a computer module that runs the method of the first aspect, or the method of the third aspect, or a combination of the above methods.

[0061] Beneficial technical effects

[0062] 1) High data security: By using the combined interference steps of DNA molecule copies with base differences and random interruptions, the present invention increases the interference in the decryption process, making it impossible for attackers to accurately obtain the correct copy of the encrypted information. This greatly increases the difficulty of decryption and improves data security.

[0063] 2) Efficient encryption and decryption process: Compared with some DNA encryption methods that rely on complex calculations, the amount of calculation required by the present invention is relatively low. The operations of random interruption and combined interference can be completed in a shorter time, which improves the efficiency of encryption and decryption.

[0064] 3) High capacity and long-term storage capability: DNA information storage has extremely high density and long-term data storage capability, which can cope with large data storage needs and maintain data integrity and reliability.

[0065] 4) Broad application prospects: The data encryption protection technology for DNA information storage of the present invention has broad application prospects in the field of data storage and protection. It can be applied to cloud storage, data backup, sensitive information storage and other fields to provide reliable protection for data security.

[0066] In summary, the present invention provides a data encryption protection technology using DNA information storage, which uses random interruption and combined interference steps to form interference in the decryption process using DNA molecule copies with base differences. Compared with the prior art, this solution has the advantages of being hidden, difficult to attack, and having lower computing requirements. This technology has broad application prospects in the field of data storage and protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 : Flow chart of the technical solution of encrypted storage and decrypted reading of the present invention (A: encryption process; B: decryption process);

[0068] Figure 2 : Schematic diagram of the principle of increasing combinatorial interference space by randomly interrupting DNA sequences;

[0069] Figure 3 :DNA fragment assembly and reconstruction flow chart;

[0070] Figure 4 : Electrophoresis analysis results of samples treated at 70 degrees for 30 days;

[0071] Figure 5 : Digital images verifying the method of this application. DETAILED DESCRIPTION

[0072] the term

[0073] DNA Fountain Code and Erasure Code

[0074] DNA The fountain code was first As reported by Erlich et al., Science 355, 950–954 (2017), this method The data file is cut into several segments by Fountain Code Algorithm Obtain the coding sequence and then convert it into The DNA sequence can be converted into a DNA sequence and can be screened by conditions such as GC content or homopolymers to eliminate unwanted sequences.

[0075] Fountain code is a type of erasure code. Erasure code itself is a coding fault-tolerant technology that was first used in the communications industry to solve the problem of partial data loss during transmission. Its basic principle is to divide the transmitted signal into segments, add certain checks, and then make certain connections between the segments. Even if part of the signal is lost during the transmission process, the receiving end can still calculate the complete information through the algorithm.

[0076] In the present invention, "data droplet", "information block", "byte sequence" and the like have the same meaning, and all refer to data fragments obtained after processing a data file through erasure coding.

[0077] DBG method and DBG diagram

[0078] De Bruijn Graph (DBG) is an anti-intuition algorithm for assembling sequencing data. It is mainly used for the assembly of short high-abundance fragments, especially the second-generation sequencing data. The DBG algorithm converts the assembly process into a problem of finding an Eulerian path in the DBG graph (starting from a certain point and passing through all edges only once). The Eulerian path is a P-type problem, that is, there are reliable necessary and sufficient conditions to prove the existence of the Eulerian path, which can be solved within a certain time. The method is as follows:

[0079] ① Split the reads into shorter k-mers of uniform length (reads shorter than k will be discarded);

[0080] ② Find the overlapping relationship between k-mers and establish a DBG graph. That is, for any two k-mers u and w, if the last k-1 base sequences of u are the same as the first k-1 base sequences of w, then establish a directed edge from u to w;

[0081] ③Find the Euler path in the DBG graph to obtain the assembly sequence.

[0082] Example

[0083] Example 1 Encryption Writing Scheme

[0084] like Figure 1 As shown in (A), the information encryption and writing of the DNA information storage encryption and decryption technology of the present invention includes the following 6 main steps:

[0085] Step 1, erasure coding: Encode the data to be encrypted into a certain number of small data droplets through fountain codes, each of which includes an index and a data carrying area; this technical solution uses fountain codes as an erasure scheme, and other erasure codes, such as Reed-Solomon (RS) codes, LDPC codes, etc., can be used as optional solutions; if a small number of data droplets are wrong, the fountain code will lead to the loss of the entire information, and the fountain code scheme is more conducive to enhancing the encryption protection strength of the information.

[0086] Step 2: Encryption and scrambling. Perform encryption operations on the data of each information droplet. This technical solution uses DES as the encryption algorithm. Other encryption algorithms such as AES (Advanced Encryption Standard) and 3DES (Triple Data Encryption Standard) can be used as optional encryption schemes.

[0087] Step 3, add ECC checksum and byte sequence scrambling. Add ECC code to each data droplet; this technical solution uses CRC32 as the ECC coding scheme for data droplets. Other ECC codes, such as RS code, can be used as optional coding schemes; in order to prevent information thieves from successfully performing ECC checks, it is necessary to pseudo-randomly scramble the sequence with the ECC code added. The index value and key of the data droplet are used as the seed value of the pseudo-random function, thereby preventing information thieves without the key from successfully performing ECC checks. The pseudo-random sequence function used in this technical solution for random byte scrambling and the corresponding three Python functions for scrambling and resetting bytes in sequence are as follows:

[0088]

[0089] Step 4: transcode the binary sequence of the data droplet into a DNA sequence. This technical solution uses the transcoding rules shown in Table 1 to convert between binary sequences and DNA sequences. Any other transcoding rules can be used as alternatives, and can achieve similar transcoding effects.

[0090] Table 1 Base bit correspondence table used in technical solution 1

[0091]

[0092] Note: Any other base-bit correspondence can achieve similar technical effects.

[0093] Step 5, synthesizing the ssDNA sequence obtained in step 4 by high-throughput DNA synthesis technology.

[0094] Step 6, random interference information introduction and combined interference enhancement. The introduction of interference information and combined interference enhancement are achieved through error-prone PCR, or high temperature degradation treatment, or ultraviolet treatment, or DNAase I enzymatic treatment, or a combination of any of the above techniques. Figure 2 The principle of increasing the combinatorial interference space by randomly interrupting the DNA sequence is demonstrated. The processed DNA sample can be used as an encrypted information medium, and the information can be protected by proper storage.

[0095] Example 2 Decryption Reading

[0096] like Figure 1 As shown in (B), the information decryption and reading of the DNA information storage encryption technology of the present invention includes the following 6 main steps:

[0097] Step 1: high-throughput sequencing, which is to perform high-throughput sequencing on the encrypted and stored DNA samples; this technical solution uses the Illumina NovaSeq sequencer for high-throughput sequencing, and the read length of double-end sequencing is 150bp*2; other sequencing technologies, such as nanopore sequencing technology, can be used as optional solutions;

[0098] Step 2: DNA fragment assembly and reconstruction; the process of assembly and reconstruction is as follows Figure 3 As shown, the detailed steps are described in Example 3;

[0099] Step 3, reconstructing the data droplet; reconstructing the encrypted data droplet through the bit-DNA sequence transcoding rules shown in Table 1;

[0100] Step 4, reordering and performing data ECC verification on the reconstructed data droplets; the ordering method and verification method are performed according to the ECC verification code and byte scrambling algorithm used in the encryption writing process;

[0101] Step 5, using the key to decode the data;

[0102] Step 6: Use fountain code to decode the original information.

[0103] Example 3 Decryption and assembly of DNA fragments

[0104] The DNA fragments (small pieces of encrypted information) corresponding to each index value are realized through the following sequence assembly process based on the Debreu graph. The sequence assembly process contains 8 core steps:

[0105] Step S1, calculating the initial k-mer of the current DNA sequence to be assembled according to the index information;

[0106] Step S2, searching for a k-mer connected to the k-mer in the Debrecen graph (DBG) graph; if not found, the assembly of the current DNA fragment fails;

[0107] Step S3, if connected k-mers are found in the DBG graph, these k-mers are placed at the end of the search path; each k-mer found forms an independent terminal k-mer node;

[0108] Step S4, judging the node, if the path length does not reach the length of the DNA fragment, repeating steps S2-S4 until the path length meets the length of the DNA fragment;

[0109] Step S5, when the path length reaches the length of the DNA sequence, the path is reordered according to the index and key information; this step is a reverse operation introduced in the encoding process to randomly shuffle the path according to the index and key information; after this step, the encrypted information bytes and CRC bytes will be returned to their original positions;

[0110] Step S6, reading the CRC value of the path-related DNA sequence and performing a CRC check;

[0111] Step S7, determine the node and the number of paths that meet the CRC check; if the number of paths is zero or greater than 1, the DNA sequence assembly process in this direction fails; if the number of paths is 1, output the relevant DNA sequence;

[0112] Step S8: If the number of paths that satisfy the CRC check is 1, the DNA sequence contained in the path is output.

[0113] After the above steps are completed, the byte strings of the corresponding indexed DNA fragments and the encrypted information blocks can be obtained.

[0114] Example 4: Experiment of introducing random errors in error-prone PCR:

[0115] All error-prone polymerase chain reactions (PCR) were performed using the "Controlled Error Polymerase Chain Reaction Kit" (CAT#: 160903-100) produced by Beijing Tianenze Biotechnology Co., Ltd. The temperature cycle parameter settings are shown in Table 2: heating at 94°C for 3 minutes; 94°C for 30 seconds, 55°C for 1 minute, 72°C for 30 seconds, repeat the thermal cycle 30 times; and finally store at 4°C.

[0116] Table 2 PCR reaction conditions

[0117]

[0118] Example 5: Random fragmentation experiment (DNAse I method):

[0119] Use a commercial DNAse I product, such as NEB DNAse I (M0303L). Incubate at 37 degrees for 1 minute according to the reaction system shown in Table 3.

[0120] Table 3 DNAse I random disruption conditions

[0121]

[0122] Example 6: Random fragment interruption experiment (high temperature degradation method):

[0123] The samples were placed at high temperatures of 70 degrees or above to accelerate the degradation of the fragments. Figure 4 The results of agarose electrophoresis analysis of samples treated at 70 degrees for 30 days are shown.

[0124] Example 7: Example of encrypted storage and decrypted reading of pictures:

[0125] This embodiment takes the encrypted storage and reading of a digital picture as an example to illustrate the entire encryption and decryption process of the present invention. Figure 5 As shown. The image size is about 308KB, MD5 (f84a4b1775e80d8f838f50f2ff0b5a67). The image is encoded into 12,000 196bp DNA sequences (Table 4 shows part of the sequence information) using a 32-bit password: 0b10101010101111011001010100110110 and the scheme of Example 1. It contains two primer sequences p1 = 'CCTGCAGAGTAGCATGTC' and p2 = 'CTGACACTGATGCATCCG'. Other parameters: Fountain code random seed value is 2, delta = 0.01, c_value = 0.01, data chunk number 10517, each DNA sequence encodes 30 bytes of information, and the initial index value is 211011011.

[0126] The encoded sequence was synthesized into an ssDNA library by a DNA synthesis company. The ssDNA synthesized by the company was used as a template, and the library was amplified based on error-prone PCR according to the method of Example 4. The amplified sequence was processed by the method of Example 6 and sent to a sequencing company for sequencing. After sequencing, the sequencing reads shown in Table 5 were generated. The sequencing reads were decrypted by the method of Example 2 with the encryption key 0b10101010101111011001010100110110, and the encrypted data ( Figure 5 ), the MD5 value of the obtained image is consistent with the original data. According to statistics, each fragment in this embodiment introduces an average of 10 4 The above interference paths greatly improve the security of encrypted data.

[0127] Table 4 Partial sequences of 12,000 DNA sequences generated by coding

[0128]

[0129]

[0130]

[0131]

[0132]

[0133] Table 5 Statistical information of sequencing data

[0134]

[0135] Q20 (Q30) refers to the percentage of bases in the sequencing sequence with a quality value greater than or equal to 20 (30), and its main function is to evaluate the accuracy of the sequence. Q20 (Q30) means that the probability of a base being mis-measured is 1% (0.1%) and the accuracy is 99% (99.9%). Generally speaking, the amount of bases with an accuracy of Q30 must be at least 85%.

Claims

1. A method for encrypting DNA storage information, comprising the following steps: Step 1, encoding small information blocks: Encode the data to be encrypted into a certain number of small information blocks through erasure coding, each data fragment includes an index and a data carrying area; Step 2, encryption: perform encryption operations on the data of each small block of information; Step 3, adding ECC checksum and scrambling the byte sequence: adding ECC code to each encrypted information block, and performing pseudo-random scrambling on the byte sequence with the ECC code added; Step 4, transcoding the byte sequence of the encrypted and scrambled information block into a DNA sequence; Step 5, synthesizing the DNA sequence obtained in step 4 by high-throughput DNA synthesis technology; Step 6: random interference information import and combined interference enhancement.

2. The DNA storage information encryption method as claimed in claim 1, wherein The erasure code in step 1 is a fountain code, a Reed-Solomon (RS) code or an LDPC code; It is preferred to use fountain codes. If a small number of data fragments are wrong, the entire information will be lost. The fountain code scheme is more conducive to enhancing the encryption protection strength of the information.

3. The DNA storage information encryption method according to claim 1, wherein: In step 2, DES, AES (Advanced Encryption Standard), and 3DES (Triple Data Encryption Standard) are used as optional encryption schemes; DES is preferably used.

4. The DNA storage information encryption method according to claim 1, wherein: In step 3, CRC32 is used as the ECC encoding scheme for the data segment; Preferably, in step 3, the index value of the information block and the key of the encryption scheme in step 2 are used as the seed value of the pseudo-random function, thereby preventing an information thief without the key from successfully performing ECC verification.

5. The DNA storage information encryption method according to claim 1, wherein: The following base-bit correspondence is used in step 4: or Or any other combination among the 24 base bit combination correspondences; and / or The DNA sequence synthesized in step 5 has a linker.

6. The DNA storage information encryption method according to claim 1, wherein: In step 6, the introduction of interference information and the enhancement of combined interference are achieved through error-prone PCR, or high temperature degradation treatment, or ultraviolet treatment, or DNAase I enzymatic treatment, or a combination of any of the above technologies.

7. A DNA library carrying encrypted information obtained by the DNA storage information encryption method as described in any one of claims 1 to 6.

8. A method for decrypting the DNA library carrying encrypted information as claimed in claim 7: Step 1, high-throughput sequencing: high-throughput sequencing of the encrypted and stored DNA samples; Step 2, DNA fragment assembly and reconstruction; Step 3, reconstructing the information block: reconstructing the scrambled and encrypted information block through the base-bit correspondence; Step 4, reordering and data ECC verification of the reconstructed information blocks; the ordering method and verification method are based on the ECC check code and pseudo-random scrambling algorithm used in the encryption writing process; Step 5, using the key to decode the reordered information blocks; Step 6, decoding the original information based on the erasure coding scheme; Preferably, in step 1, high-throughput sequencing is performed using an Illumina sequencer, with a read length of 150 bp*2 for double-end sequencing, or nanopore sequencing is used; Preferably, step 3 adopts the following base-bit correspondence: or Or any other combination among the 24 base bit combination correspondences; Preferably, the steps 2) to 4) are an assembly method based on a Debret diagram, specifically comprising: Step S1, calculating the initial k-mer of the current DNA sequence to be assembled according to the index information; Step S2, searching for a k-mer connected to the k-mer in the Debrecen graph (DBG) graph; if not found, the assembly of the current DNA fragment fails; Step S3, if connected k-mers are found in the DBG graph, these k-mers are placed at the end of the search path; each k-mer found forms an independent terminal k-mer node; Step S4, judging the node, if the path length does not reach the length of the DNA fragment, repeating steps S2-S4 until the path length meets the length of the DNA fragment; Step S5, when the path length reaches the length of the DNA sequence, the path is reordered according to the index and key information; This step is a reverse operation of the encoding process that randomly scrambles the path based on the index and key information. After this step, the encrypted information bytes and ECC bytes will be returned to their original positions. Step S6, reading the ECC value of the path-related DNA sequence and performing ECC verification; Step S7, determining the node, determining the number of paths that meet the ECC check; If the number of paths is zero or greater than 1, the DNA sequence assembly process in that direction fails; If the number of paths is 1, the relevant DNA sequence is output; Step S8, if the number of paths that meet the ECC check is 1, then output the DNA sequence contained in the path; After the above steps are completed, the corresponding indexed DNA fragments and encrypted information blocks can be obtained.

9. A computer module that executes the method of any one of claims 1 to 7, or the method of claim 8, or a combination of the above methods.

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