| 摘要 |
PROBLEM TO BE SOLVED: To provide a new variation method with which three continuous bases of a gene encoding a protein are randomly and in an approximately constant variation ratio substituted with another base sequence having a specific sequence to obtain an anchor therefor, and to provide a method for simply producing variant gene libraries and variant proteins. SOLUTION: This method for DNA variation is characterized in that a DNA is subjected to ring formation to prepare a ring-shaped single-stranded DNA, an arbitrary one site of the ring-shaped DNA is cleft, anchors are bonded to both the ends of the obtained chained single-stranded DNA, the DNA is amplified by a PCR method, then the outside of a recognition sequence in the anchors is cleft by using a restriction enzyme to cleave the DNA at the outside of the recognition sequence, a specific base sequence prepared in the anchor is made to be inserted into the end of one side and a base sequence having the same number of bases as those inserted into the one side is deleted at another side. The anchor therefor is obtained. A variant DNA and a variant protein library are obtained by the method. |
