Identification of A Novel Missense Mutation in The Norrie Disease Gene: The First Molecular Genetic Analysis and Prenatal Diagnosis of Norrie Disease in An Iranian Family.

Norrie disease (ND) is a rare X-linked recessive disorder, which is characterized by congenital blindness and, in several cases, accompanied with mental retardation and deafness. ND is caused by mutations in NDP, located on the proximal short arm of the X chromosome (Xp11.3). The disease has been observed in many ethnic groups worldwide, however, no such case has been reported from Iran. In this study, we present the molecular analysis of two patients with ND and the subsequent prenatal diagnosis. Screening of NDP identified a hemizygous missense mutation (p.Ser133Cys) in the affected male siblings of the family. The mother was the carrier for the mutation (p.Ser133Cys). In a subsequent chorionic amniotic pregnancy, we carried out prenatal diagnosis by sequencing NDP in the chorionic villi sample at 11 weeks of gestation. The fetus was carrying the mutation and thus unaffected. This is the first mutation report and prenatal diagnosis of an Iranian family with ND, and highlights the importance of prenatal diagnostic screening of this congenital disorder and relevant genetic counseling.