You identified a virus and extracted its genome nucleic acid

You identified a virus and extracted its genome (nucleic acid). Using biochemical methods, you found that the base composition of its genome is 25% A, 33% T, 24% G, and 18% C. Based on this discovery, would you predict that the genome of the virus is double strand DNA? And why?

Solution

The virus is not a double stranded DNA because it is not following Chargaff\'s rule of base pairing.Hence,the viral genome is not double stranded,but is single stranded DNA.

According to Chargaff\'s Rule,in a Double stranded DNA molecule,purines and pyrimidines must be in equal composition,i e,guanine equals to cytosine units and the number of adenine equals to the number of thymine.

In this case,A is 25% and T is 33%,hence A not equal to T. Similarly G is 24% and C is 18%,hence G not equal to C. As it is not following Chargaff\'s rule,it cannot be a double stranded DNA.