Point mutation is the mutation that affects a single nucleotide or nucleic acid. It commonly occurs when one base is substituted for the other. It may also result due to insertion and deletion of a single base pair.
Examples of point mutation are:
- Cystic fibrosis: It occurs due to the deletion of three nucleotides in the CFTR gene. In this, an amino acid phenylalanine is lost which causes misfolding of protein.
- Sickle cell anemia: It is caused by single point mutation in the beta haemoglobin gene. This results in the conversion of GAG codon into GUG that encodes amino acid valine.