Answer :
Ans.
The chromosomes are made up of DNA and protein molecules. DNA gets transcribed into mRNA that further gets translated into proteins. The mRNA has 61 codons (made of three nucleotide bases) for a particular amino acids, and 3 stop codons that stop the synthesis of protein molecule and cause termination of translation. Stop codons include UAA, UAG, UGA, where A is adenine, U is uracil, and G is guanine base.
Thus, if an individual has inherited a non-functional protein that really does say stop whenever the enzyme gets synthesized, adenine, guanine, or thymine (as thymine is present in DNA instead of uracil) bases can be found in his DNA to get arranged to form stop codons.