Patent ID: 9574188
Date: 2017-02-21
CPC Classifications: C12N,C12Q

Claim:
1. A method of making an adapter-tagged restriction library comprising: providing a double-stranded DNA oligonucleotide which is a twin adapter containing a recognition site of a first restriction enzyme (first RE); digesting the twin adapter with the first RE, resulting in two adapters with the same restriction fragment end; digesting a genomic DNA with at least a second restriction enzyme (second RE), wherein the digestion by the second RE results in the genomic DNA being broken into a plurality of restriction fragments, wherein the second RE has a recognition site different from that of the first RE, yet after digestion leaves the same restriction fragment end as that of the first RE; ligating with a DNA ligase the digested twin adapter to one end or each end of the plurality of restriction fragments, resulting in a mixture of a self-ligation product and a hetero-ligation product; repeating the ligating and digesting steps multiple times as needed with the mixture of a self-ligation product and a hetero-ligation product, to make the adapter-tagged restriction library substantially free of the self-ligation product, wherein the repeated digesting step is the step of digesting the mixture of a self-ligation product and a hetero-ligation product with the first RE or the second RE, wherein the first RE or the second RE can cleave the self-ligation product and is incapable of cleaving the hetero-ligation product, and wherein the repeated digesting and ligating steps result in the hetero-ligation product substantially free of the self-ligation product.