Gene target region enrichment method and kit

A method for enriching target regions of gene(s), comprising:

• (1) amplifying fragmented DNA comprising the target region(s) via specific probes to provide captured-extension products, wherein the specific probe comprises a sequence complementary to the target region of the fragmented DNA, and the 3′terminal nucleotide of the specific probe is modified to prevent a ligation reaction at the 3′ terminal of the specific probe;
• (2) linking the 3′ terminal of the captured-extension product obtained in step (1) to linker DNA to obtain a ligation product,
• the amplification system of step (1) includes a high-fidelity DNA polymerase with 3′-5′ exonuclease activity and dNTP,
• the 3′ terminal of the specific probe is modified by C3 Spacer,
• the C3 Spacer is excised from the 3′ terminal of the specific probe by high fidelity-DNA polymerase after the specific probe binds to the target regions of the fragmented DNA,
• the linker DNA is modified by phosphate group at the 5′ terminal and the hydroxyl group at the 3′ terminal is replaced by C3 Spacer.