Intermediate CAG repeat lengths (53,54) for MJD/SCA3 are associated with an abnormal phenotype.

We report on a Dutch family in which 4 members in 2 generations have intermediate repeat lengths (53 and 54) for Machado-Joseph Disease/Spinocerebellar Ataxia (MJD/SCA3). All but the youngest have a restless legs syndrome with fasciculations and a sensorimotor axonal polyneuropathy. Central neurological abnormalities are only present in 2. This family shows that intermediate repeat lengths can be pathogenic and may predispose for restless legs and peripheral nerve disorder.