What amino acid does the human body use to synthesize melanin?

Amino acids are the building blocks used to make proteins in the body. In the human body, 20 amino acids are encoded in the DNA. These are transcribed into messenger RNA and translated into proteins. The sequence of amino acids defines the primary structure of a protein. In some instances biomolecules like the melanins can be synthesized from one amino acid before post-translational modification.

There are three basic types of melanin: eumelanin, pheomelanin, and neuromelanin.

Melanins, chemically-synthesized pigment molecules, are produced by the oxidation of the amino acid tyrosine, followed by its polymerization. This pigment molecule is produced in a specialized group of cells known as melanocytes. The initial step of the biosynthetic pathway for melanins is catalysed by tyrosinase.