Mutation detection in an equivocal case of Friedreich's ataxia

Compound heterozygosity at the Friedreich's ataxia locus accounts for approximately 2% of molecularly confirmed cases. Genotype-phenotype correlation in this subgroup of patients reveals a spectrum of clinical variability. This report describes the clinical and molecular findings in a 6-year-old patient with Friedreich's ataxia who carried a pathologic GAA expansion of approximately 1,000 repeats on one allele and a novel initiation codon point mutation (3G-->A) on the other.