Patent ID: 6924104

Claim:
A method to selectively amplify or recover heterohybrid DNA molecules resulting from mixing, denaturating, and reannealing two or more DNA pools, wherein each of the pools comprises DNA from a different individual or a mixture of DNA from multiple individuals comprising: ligating first Y-shaped adapters onto a first pool of restriction endonuclease digested DNA molecules, wherein the first Y-shaped adapters comprise a complementary and a non-complementary end, said non-complementary end comprising a 5′ terminal sequence of a first DNA strand that is non-complementary to a 3′ terminal sequence of a second DNA strand, and wherein the 5′-terminal sequence is longer than said 3′-terminal sequence; ligating second Y-shaped adapters onto a second pool of restriction endonuclease digested DNA molecules, wherein the second Y-shaped adapters comprise a complementary and a non-complementary end, said non-complementary end comprising a 5′ terminal sequence of a first DNA strand that is non-complementary to a 3′ terminal sequence of a second DNA strand, wherein the 5′ terminal sequence is longer than the 3′ terminal sequence, wherein said 5′-terminal sequence of the second Y-shaped adapters is longer than said 3′-terminal sequence of the second Y-shaped adapters, and wherein the 3′ terminal sequence of the first Y-shaped adapters is complementary to said 5′ terminal sequence of the second Y-shaped adapters and the 3′ terminal sequence of said second Y-shaped adapters is complementary to said 5′ terminal sequence of said first Y-shaped adapters; mixing, denaturing, and reannealing the first pool ligated to the first adapter with the second pool ligated to the second adapter to form a mixture containing heterohybrids and homohybrids; extending complementary 3′ terminal nucleotides of the heterohybrids using a DNA polymerase that lacks a 3′-5′ exonuclease activity to form new 3′ ends on the heterohybrids; and amplifying the heterohybrids in the mixture using first and second primers complementary, to the new 3′ ends, whereby the heterohybrids are selectively enriched in the mixture containing heterohybrids and homohybrids.