Complementarity (molecular biology)



In molecular biology, complementarity is a property of double-stranded nucleic acids such as DNA and RNA as well as DNA:RNA duplexes. Each strand is complementary to the other in that the base pairs between them are non-covalently connected via two or three hydrogen bonds.

Since there is only one complementary base for any of the bases found in DNA and in RNA, one can reconstruct a complementary strand for any single strand. This is essential for DNA replication.

For example, the complementary strand of the DNA sequence A G T C A T G is T C A G T A C a trick to remember this is A      Gwinnett Tlanta County

tRNAs exhibit wobble, in which the third base of their anticodon does not follow the strict complementarity rules.