Caterina Mariotti, Alessandro Filla, Cinzia Gellera, Giovanni Coppola, Elena Salvatore, M. C. Riggio, G. De Michele, S. Di Donato, Imma Castaldo, Giuseppe Caruso, Sergio Cocozza, Davide Pareyson, O. Calabrese, Filla, Alessandro, Mariotti, C, Caruso, G, Coppola, G, Cocozza, Sergio, Castaldo, I, Calabrese, O, Salvatore, Elena, DE MICHELE, Giuseppe, Riggio, Mc, Pareyson, D, Gellera, C, and DI DONATO, S.
Two hundred and forty-eight patients from 116 Italian families with dominant ataxia were studied for CAG expansion within SCA1, 2, 3, 6, 7 (spinocerebellar ataxia) and DRPLA (dentatorubropallidoluysian atrophy) genes. Fifty-six percent of the families originated from Southern, 19% from Central and 25% from Northern Italy. SCA2 was the commonest mutation, accounting for 47% of the families, followed by SCA1 (24%), SCA6 (2%), SCA7 (2%) and DRPLA (1%). No SCA3 family was found. Twenty-four percent of the families carried a still unidentified mutation. When occurrence of mutations was evaluated according to the geographic origin, SCA1 was the commonest in Northern (72%), whereas SCA2 was prevalent (63%) in Southern Italy. The number of CAG repeats in SCA1 normal alleles was higher in Northern than in Central-Southern Italy.