The genetic ascertainment of multiple endocrine neoplasia type 1 syndrome by ancient DNA analysis

Abstract

Multiple endocrine neoplasia type 1 (MEN1) is a rare autosomal dominant inherited endocrine cancer syndrome characterised by parathyroid, pancreas, and anterior pituitary tumors. The disease responsible gene, MEN1, was identified in 1997 and localizes to chromosome 11q13 in a minimal 600 kb interval between PYGM and D11S449 loci. About 10-20% of MEN1 patients do not have any mutation in the coding region and/or in the exon-intron junctions of the MEN1 gene. In this case, familial haplotype analysis of the 11q13 region, in at least two generations of affected members, is the only possible genetic ascertainment of the disease. We performed a microsatellite haplotype analysis at 11q13 region in 8 living and 1 deceased member of a MEN1 Italian family without any detected germline mutation of the MEN1 gene. The application of forensic techniques for ancient DNA analysis made it possible to identify the familial disease-associated haplotype and demonstrated that MEN1 disease haplotype family history can be reconstructed even when one or more family members are deceased. Identification of MEN1 disease haplotype is helpful in the clinical management of patients and relatives in families without any mutation of the MEN1 gene. Genetic screening allows the identification of individuals who are at risk before the development of clinical symptoms, limiting invasive annual cancer surveillance only to genetically positive individuals and making it possible to avoid further clinical screenings in non-carriers.