Two Sequences Variations of the E768D Mutation Found in Familial Medullary Thyroid Carcinomas

Abstract

Medullary thyroid cancer or MTC is present in sporadic form (75% of cases) and in familial form (25% of cases), in this latter situation, the MTC is a part of Multiple Endocrine Neoplasia type 2 (MEN 2). The MEN2 is divided into MEN2A, MEN2B and FMTC or isolated familial MTC. The MEN2 are rare hereditary disease, transmitted as an autosomal dominant mode, linked to mutations of the RET gene. The discovery of a mutation in the RET proto-oncogene by molecular biology techniques in a index case of MTC confirms the diagnosis of familial and allows the genetic testing of healthy clinically related index case: those who carry the genetic mutation, will be offered prophylactic thyroidectomy before any biological or clinical manifestation. The genetic analysis of the RET gene was performed by PCR / sequencing. The E768D mutation was found in the exon 13 of the RET gene in 2 differences sequences forms (GAG/GAC et GAG/GAT). This mutation, already described, found in the FMTC.