To determine whether the MSI is also evident in human FA patients harboring mutations in FANCJ, we obtained primary lymphoblastoid cell lines (LCLs) from affected and unaffected members of a second-degree consanguineous FA-J family (two unaffected parents and three affected children), with affected individuals carrying a large autozygous region on chromosome 17, including FANCJ/BRIP1, and homozygous for the missense mutation c.1878A>T (exon 13 of FANCJ) with the effect p.E626D, which destabilizes the protein. The gene discussed is BRIP1; the disease is Friedreich ataxia.