describe how a genetic mutation of the gene coding for lactase can lead to lactose intolerance.

-A genetic mutation within the lactase gene, for example base substitution, changes a codon -This codon codes for a different amino acid to be transcribed and translated-Therefore the sequence of amino acids(primary structure) in the polypeptide is altered -This causes the polypeptide to fold differently (tertiary structure), therefore changing the shape of the enzyme active site.-The shape of the active site is specific to lactose.-The substrate (lactose) is no longer complementary to the active site, and so no enzyme-substrate complexes are formed, and the lactose cannot be broken down, causing lactose intolerance.