1. Non-Communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran 2. Medical-Genetic Counseling Center, Alborz Welfare Organization, Karaj, Iran . National Institute of Genetic Engineering
Abstract
Introduction
Oculocutaneous albinism type 1 is characterized by hypopigmentation of the skin and hair and the distinctive ocular changes found in all types of the albinism, including: nystagmus; reduced iris pigment with iris translucency; reduced retinal pigment with visualization of the choroidal blood vessels on ophthalmoscopic examination; foveal hypoplasia with substantial reduction in visual acuity; and misrouting of the optic nerve fiber radiations at the chiasm, resulting in strabismus. oca1 is inherited in autosomal recessive manner. this study was designed to find the genetic defect in a 30 years-old affected female, having non-consanguineous parents, who was married with an apparently normal non-consanguineous male.
Methods
Sanger sequencing of the tyr gene was performed for the affected individual and her husband.
Results
Sanger sequencing of the tyr gene was performed for the affected individual. she was homozygote for a pathogenic variant in tyr gene (c.996g>a, p.m332i). sanger sequencing of the tyr gene for her husband showed, he was heterozygote for an another pathogenic variant in tyr gene (p. arg402gln)
Conclusion
This indicates that there is a significant recurrence risk 50%, even these couple are non-consanguineous, in form of compound heterozygote. because this is an autosomal recessive, resembles a pseudo-dominant inheritance in their children. therefore, we can exactly determine these two different known mutations in their pregnancy product and prevent from this disease via pre implantation genetic diagnosis (pgd)
