He inherited the c.2860C > T (p.Arg954Trp) mutation in KIF21A from his mother, who also had CFEOM1, and the c.745delC (p.Leu249TyrfsX22) mutation in PAX6 from his father who had congenital aniridia. This evidence concerns the gene KIF21A and congenital fibrosis of extraocular muscles.