Immunogenetic heterogeneity of multiple sclerosis in Sardinia

Multiple sclerosis (MS) predisposition is thought to be influenced by a com plex, yet unclear interaction of genetic and environmental factors. Studyin g ethnically selected populations may reduce genetic and environmental hete rogeneities and help clarify the underlying mechanisms of MS susceptibility . Sardinians kept a homogeneous genetic structure and have among the highes t MS frequency rates worldwide. Interestingly, MS in Sardinia is linked to otherwise rare HLA alleles. In this light, recent findings from epidemiolog ical and immunogenetic studies of Sardinian MS are presented. Results confi rm that, likely due to significant genetic differences at a microgeographic level, even in this homogeneous population MS is immunogenetically heterog eneous and tends to preferentially cluster in some more archaic areas of th e island.