Suppose a person has one single mutation in their DNA and the first codon for the insulin gene now reads TAT instead of TAG. Using your codon chart, look up the amino acid that is coded for by the mutant DNA.
Using a codon chart, the gene TAT corresponds with AUA. U is Uracil and stands in place for Thymine since RNA does not use it. AUA results in the amino acid Isoleucine.
