changes in proteins due to mutations

• • Nonsense mutations: change an amino acid to a stop codon→ very noticeable effect on protein as cut short→ protein non-functional majority affecting phenotype
• • Missense mutation: point mutations resulting in amino acid change. The functionality of the resulting protein is determined if/if not the replacement amino acid is the same type as the original. The protein end product is changed and less functional e.g sickle cell anaemia
• • Silent mutations: changes in DNA sequence that do not cause a change in amino acid as redundancy of genetic code has no effect on protein. Do not have a noticeable effect on protein or phenotype
• • Neutral mutations: changes in DNA resulting in amino acid of the same type as the original so change does not significantly affect the structure of protein