Subsequence sequencing of DNA from unrelated affected individuals referred to the MRC Human Genetics Unit Eye Malformations Study identified an individual with sporadic partial aniridia and microphthalmia (Family 1434: II:1, Fig 1A and 1C) associated with de novo occurrence of MAB21L1 c.152G>T p.(Arg51Leu) (ENST00000379919.6:c.152G>T, ENSP00000369251.4:p.Arg51Leu: Sift; Deleterious (0), PolyPhen; Probably damaging (0.999), CADD 29.6, REVEL 0.682). The gene discussed is MAB21L1; the disease is isolated aniridia.