Valor clínico del análisis del ADN en familias con síndrome de neoplasia endocrina múltiple tipo IIA (MEN IIA)

Introduction. The syndrome of multiple endocrine neoplasia type IIA (MEN IIA) is an autosomal dominant disease characterized by the association of medullary thyroid carcinoma (MTC), pheochromocytoma and hyperparathyroidism. The gene responsible for this syndrome was mapped to the 10q 11.2 chromosomal region of the RET oncogene.
Objective. The objective of this report is to present our experience in the use of DNA analysis in the diagnosis of MEN IIA in two families treated in our service.
Patients and methods. The study dealt with two MEN IIA families comprised of a total of 14 members: 9 with the disease and 5 healthy at the time of the study according to the analysis of DNA extracted from peripheral blood. Exons 10 and 11 of the RET oncogene were amplified in genomic DNA by polymerase chain reaction (PCR) and mutations were detected by means of single-strand conformation polymorphism (SSCP) analysis.
Results. The mutation responsible for MEN IIA was located at codon 634 of exon 11 in both families studied here.
Conclusions.. The diagnosis of MEN IIA by detecting the mutation of the RET oncogene in the DNA of the patients has certain advantages over other methods of screening employed to date.