Its presence has also been used to explain the milder retinopathy evident in one member of a pedigree harbouring three separate CRB1 alleles—the individual with early onset RP (III:6) was homozygous for p.(Cys948Tyr), while her sister (III:4), who exhibited late-onset disease and a slower progression, carried the in-frame deletion (p.(Ile167_Gly169del)) paired with p.(Cys948Tyr) [27]. The gene discussed is CRB1; the disease is retinitis pigmentosa 1.