Homozygous or heteroallelic germline mutations in several HR genes have been described in FA subgroups, namely, BRCA1 (FA-S), BRCA2 (FA-D1), PALB2 (FA-N), RAD51C (FA-O), XRCC2 (FA-U) and RAD51 (FA-R). The gene discussed is RAD51; the disease is Friedreich ataxia.