Friedreich ataxia (FA) is caused by a GAA expansion in the first intron of the frataxin gene (FXN) in 96% of the affected individuals. The remaining patients have a GAA expansion in one allele and a point mutation in the other. Little is known about compound heterozygous patients outside Europe and North America. This group has designed a study to determine the frequency and mutational profile of these patients in Brazil. They recruited all patients with ataxia and at least one expanded GAA allele at FXN from 3 national reference centers and identified those subjects with a single expansion and completed further genetic testing. There were 143 unrelated patients (128 families), five of which had a single expanded allele. They identified point mutations in three out of these five (3/128 = 2.34%). Two patients had the c.157delC variant, whereas one individual had the novel variant c.482+1G>T. These results indicate that FXN point mutations are rare, but exist in Brazilian patients with FRDA. This has obvious implications for diagnostic testing and genetic counseling.

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