A novel 5-bp deletion in Clarin 1 in a family with Usher syndrome.

ABSTRACT

BACKGROUND: To identify the genetic defect in a Lebanese family with two sibs diagnosed with Usher Syndrome. MATERIALS AND METHODS: Exome capture and sequencing were performed on DNA from one affected member using Agilent in solution bead capture, followed by Illumina sequencing. RESULTS: This analysis revealed the presence of a novel homozygous 5-bp deletion, in Clarin 1 (CLRN1), a known gene responsible for Usher syndrome type III. The deletion is inherited from both parents and segregates with the disease phenotype in the family. The 5-bp deletion, c.301_305delGTCAT, p.Val101SerfsX27, is predicted to result in a frameshift and protein truncation after 27 amino acids. Sequencing all the coding regions of the CLRN1 gene in the proband did not reveal any other mutation or variant. CONCLUSION: Here we describe a novel deletion in CLRN1. Our data support previously reported intra familial variability in the clinical features of Usher syndrome type I and III.