The invention relates to the technical field of animal genetic breeding and
genetic engineering, in particular to an sgRNA molecule, a cattle DDX58
gene single base
mutation system, a construction method and application. And the
molecular sequence of the sgRNA is as shown in SEQ ID NO. 3. According to the method, sgRNA shown in SEQ ID NO.3 is subjected to specific
chemical modification, CBE mRNA obtained through in-vitro transcription is jointly delivered to a cattle fertilized egg, the cattle congenital immune key
gene DDX58 is precisely edited, finally, the
gene edited
disease-resistant cattle is obtained, the editing efficiency is high, and the off-target risk is reduced. According to the method, the
toxicity problem related to
DNA delivery does not exist, a simple, convenient and effective way is provided for simplifying the
genome editing development process, the application value of
chemical synthesis of sgRNA in
genome editing is proved, and wide application of the
CRISPR-Cas technology in the fields of
biotechnology and treatment is expected to be accelerated.