Mutations in the POLG1 gene are not a relevant cause of cerebellar ataxia in Italy

Mutations in the POLG1 gene, encoding the catalytic subunit of the mitochondrial DNA polymerase ?, have recently been reported in autosomal recessive and sporadic cases with cerebellar ataxia. These patients are often homozygotes for the Trp748Ser mutation or compound heterozygotes for Trp748Ser and Ala467Thr. Other less common mutations associated with ataxia are Gln497His, Arg627Trp, Pro648Arg, Arg807Cys, His932Tyr, and Gly1051Arg. We studied 257 consecutive Italian probands referred to our diagnostic center for genetic testing of SCA (227 sporadic, and 30 with a possible familiarity). The screening for the above mutations did not identify any carrier. Our findings suggest that POLG1 mutations do not represent a major determinant for the pathogenesis of cerebellar ataxias in the Italian population.