Missense mutation

In genetics, missense mutations or nonsynonymous mutations are types of point mutations where a single nucleotide is changed to cause substitution of a different amino acid. This in turn can render the resulting protein nonfunctional. Such mutations are responsible for diseases such as Epidermolysis bullosa, sickle-cell disease, and SOD1 mediated ALS.
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A genetic change that results in the substitution of one amino acid in protein for another. A missense mutation is responsible for sickle hemoglobin, the molecular basis of sickle cell trait and sickle cell anemia.

A mutation that causes the substitution of one amino acid for another (non-synonymous change). An example is the major HFE mutation C282Y in which results in an amino acid change at position 282.