IS THE MISMATCH REPAIR-DEFICIENT TYPE OF MUIR-TORRE SYNDROME CONFINEDTO MUTATIONS IN THE HMSH2 GENE

The Muir-Torre syndrome (MTS) is a rare autosomal-dominant condition c haracterized by the occurrence of sebaceous skin lesions and internal rumours in a patient. It has been demonstrated that at least a subgrou p of MTS exhibits clinical and molecular genetic features of hereditar y nonpolyposis colorectal cancer, including microsatellite instability in skin and visceral rumours, because of mutations in DNA mismatch re pair genes. We have identified germline mutations in the hMSH2 gene in two unrelated MTS patients ascertained because of their skin rumours. Our results, together with published MTS cases, support the hypothesi s that MTS with its characteristic skin lesions is confined to mutatio ns in the hMSH2 gene.