A missense mutation occurs when there is a mistake in the DNA code and one of the DNA base pairs is changed, for example, A is swapped for C. This single change means that the DNA now encodes for a different amino acid, known as a substitution.

How often do missense mutations occur?

The most numerous class of protein-altering mutations is missense mutations, where a single codon is altered to encode a different amino acid. On average, 2% of people carry a missense mutation in any given gene (2).

What happens in missense point mutation?

A missense mutation is when the change of a single base pair causes the substitution of a different amino acid in the resulting protein. This amino acid substitution may have no effect, or it may render the protein nonfunctional.