Genetic linkage analyses in 11 patients from 6 families with Friedreich’s ataxia (FA) phenotype, including cardiomyopathy, but retained reflexes (FARR), are reported from the University of Naples and C Besta Neurological Institute, Milan, Italy; and La Fe University Hospital, Spain. Mean age of onset was 13.5 years. Inheritance was autosomal recessive. All patients had progressive ataxia, dysarthria, dysmetria, scoliosis and pes cavus. FARR mapped to the FA locus on chromosome 9q 13-21.1, suggesting that FARR is a variant phenotype of FA. [1]
COMMENT. The diagnosis of FARR, a variant of Friedreich’s ataxia, should be considered in patients with early onset cerebellar ataxia, cardiomyopathy, and sensory neuropathy. Barbeau found absence of deep tendon reflexes to be a required criterion in the diagnosis of FA [2], whereas Bell and Carmichael allowed hyperactive reflexes in some cases. (Bala V Manyam, personal communication). [3]