Chargaff's rules

Chargaff rules state that the DNA of every organism should display a 1:1 ratio of certain nucleotide base residues. Namely that the number of thymine bases should equal the number of adenine, and the number of guanine bases should equal the number of cytosine. This is a consequence of base pairing. These rules were founded in 1950 by Austrian chemist Erwin Chargaff.