互補的核苷酸的相互作用。由于DNA是一種通過互補作用形成的雙鏈結構（C和G，A和T），當互補鏈被打斷時就會發生重新相互連接或雜交。若有相配的堿基序列，這種情況會發生在DNA和RNA鏈之間。雜交可以發生在包括復制、轉錄在內的所有DNA反應中，是Southern和Northern,PCR以及測序的分子生物學基礎。

The interaction of complementary nucleic acid strands. Since DNA is a double-stranded structure held together by complementary interactions (in which C always binds to G, and A to T), complementary strands favorably reanneal or “hybridize” to each other when separated. This can occur between two DNA strands and also between DNA and RNA strands provided there is sufficient complementarity in their base sequence. Hybridization occurs in all physiological DNA reactions including replication, and transcription, and forms the basis of many molecular biology techniques including Southern and Northern blotting, PCR and sequencing.