What does Chargaffs rule state?

Answer 1

In 1949 Chargaff proposed several rules. Which are as follows;

1. the total number of purine nucleotide(A+G) is equal to the total number of pyrimidine nucleotide(C+T),i.e.(A+G)/C+T)=1;A+G+T+C=1(in terms of molecular fraction)
2. the amount of adenine (A) is always equal to the thymine(T):A=T or A/T=1
3. the amount of guanine (G) is always equal to the cytosine(C):G=C or G/C=1
4. in the bases constitute of DNA ,the number of 6-amino group is equal to the number of 6-keto groups;G+T=A+T
5. the numbers (A+T) and (G+C) are the only variables .

Answer 2

Chargaff's rule states that in any species there is an equal number of A and T bases, and an equal number of G and C bases.