Copyright 2006, The Endocrine Society. Overview of the known germline missense mutations in the RET gene and their associated human diseases. The structure of the RET mRNA and the RET protein are depicted schematically. The mutations responsible for the diverse inherited cancer syndromes and the location of the mutations relative to the exons and the functional domains are shown. The most common mutations that are found in about 95% of MEN 2A and FMTC cases are depicted in bold, and MEN 2B mutations are depicted in italics. CLA, Cutaneous lichen amyloidosis. [Adapted from De Groot et al. ].