Abstract
Purpose :
To localize and identify the gene and mutations causing a Leber congenital amaurosis (LCA) in a Tunisian family
Methods :
We performed a clinical and molecular genetic study of a consanguineous Tunisian family with two individuals affected with LCA. DNA sample from the index patient was subjected to whole exome sequencing (WES). Variants localized in homozygous regions were validated by Sanger sequencing. Familial segregation was performed.
Results :
The index patient was 30 years old and reported congenital nystagmus. Night blindness and visual loss appeared during first years of life. Visual acuity was limited to hand motion. Fundus examination revealed bone spicule-shaped pigment deposits in the mid-periphery along with atrophy of the retina, narrowing of the vessels and waxy optic discs. Electroretinogram was unrecordable in both scotopic and photopic conditions. Homozygosity mapping and WES identified a homozygous genomic region harboring RPGRIP1. Sequencing analysis revealed a homozygous c.3113_3114delCT mutation of RPGRIP1 in both patients. The deletion results in a frameshift change p.(T1038Rfs*8).
Conclusions :
We identified a novel mutation p.(T1038Rfs*8), in a Tunisian family with LCA. This mutation expands the mutation spectrum of RPGRIP1 and helps to further study molecular pathogenesis of LCA.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.