Question

A mutated allele is a variant of the original “wild type” allele. A mutated allele can

mutate again. The first mutation discovered receives the primary code for that locus,

for example, 1xxxxx.

How do we code for other mutations at the same gene locus when they are found?

Please give an example.

Answer 1

Mutations occur in the DNA (genome). The replicates by the process of "Replication" to form more copies of same DNA. If mutation is there in the original strand of DNA then it is continued in the future. From DNA, RNA is produced bt the process of "Transcription". The RNA encodes all the information in form of proteins which are composed of amino acids. Proteins are produced from RNA by the process of 'Translation". If wild type DNA has some mutations then same is translated into the final proteins which encode enzymes/receptors/ proteins /hormones etc.

In the protein, amino acids join all together to form a big protein. Three bases (purines or pyrimidines- resulting in nucleotides) form a codon and produce a particular specific amino acid in the protein. For example at position 226, in the wild type animo acid methionine is there i.e. M226. If mutation occurs at 226 position and the codon now produces alanine then the denotion changes to M226A, If mutation occurs again and now the codon prouces proline then, denotion again changes to M226P.

Like wise , the codon, if mutated will lead to formation of different amino acid and denotion will change as the wildtype amino acid will always be presented first and then the number of codon where mutation has occured and then the mutated amino acid.