Question

What diseases are caused by point mutations?

Answer 1

Point mutation: It is a mutation that affects a single nucleotide or nucleic acid and happens most typically when one base is swapped for the other.

Diseases caused by point mutation are:

Sickle cell anemia:

1. It results from a point mutation where the amino acid residue glutamic acid is replaced by valine at the sixth position.
2. This causes a mutation in the beta-globin chain.
3. The patients thus have erythrocytes with lesser oxygen-carrying capacity as they become mutated and take on a sickle shape. It is an autosomal recessive disorder.

Cystic fibrosis:

1. Cystic fibrosis is caused by mutations in the gene that produces the cystic fibrosis transmembrane conductance regulator (CFTR) protein.
2. This protein under normal conditions is required for the passage of chloride and sodium ions.
3. Upon mutation, it becomes permeable and allows thick mucus to line the respiratory pathways.