Family members of patients with FA who are heterozygous carriers of PV in genes from the fourth module FANCD1 (BRCA2), FANCJ (BRIP1), FANCN (PALB2), FANCO (RAD51C) and FANCS (BRCA1) (Figure 1) are at increased risk to develop cancer [2,21]. The gene discussed is RAD51C; the disease is Friedreich ataxia.