METHOD FOR PREPARING RANDOM SGRNA LIBRARY OF TARGET SEQUENCE BY MEANS OF ENZYMATIC METHOD

Provided in the present invention is a method for preparing a random sgRNA library of a target sequence by means of an enzymatic method. The preparation method comprises the steps of: nicking a PAM region of the target sequence of sample DNA with a random nickase Nt.CviPII; linking the fragmented DNA to a linker magnetic bead containing a BbsI enzyme cleavage site; performing cleavage with BbsI to release DNA; performing random primer extension; linking same to an sgRNA skeleton containing an MmeI enzyme cleavage site; performing cleavage with MmeI to release a protospacer region; linking same to a T7 promoter sequence; performing amplification to obtain an sgRNA library template containing the T7 promoter; and finally obtaining the sgRNA library by means of in vitro transcription. According to the method for preparing a random sgRNA library of a target sequence by means of an enzymatic method in the present application, all sgRNA groups randomly covering a target region can be prepared at one time, and the m