Test Details: Medullary Thyroid Carcinoma (MTC) of the thyroid constitutes 5-10% of all thyroid carcinomas, arising from the C cells of the thyroid, of neural crest origin. Germ-line activating point mutation in the RET proto-oncogene are associated with the pathogenesis of familial MTC. The detection of RET gene mutations in apparent sporadic MTC patients has been reported from 10% to greater than 50% in different population. The hereditary type is classified as Multiple Endocrine Neoplasia (MEN2) and subclassifed as MEN 2A (probability of a DE novo mutation 5% or less), MEN 2B (probability of a DE novo mutation 50%) and Familial Medullary Thyroid Carcinoma. Since this disorder can be genetically inherited, family member of a patient with mutation in RET proto-oncogene can be tested for that particular exon.