Two Italian families with ITPR1 gene deletion presenting a broader phenotype of SCA15.

Spinocerebellar ataxia type15 (SCA15) is a pure ataxia characterized by very slow progression. Only seven families have been identified worldwide, in which partial deletions and a missense mutation of the inositol triphosphate receptor type I gene (ITPR1) have been reported. We examined a four-generation Italian family segregating an autosomal dominant cerebellar ataxia, in which linkage analysis was positive for the SCA15 locus.