Ciliome resequencing: A lifeline for molecular diagnosis in LCA
© Perrault et al. 2015
Published: 13 July 2015
Leber congenital amaurosis (LCA) is the earliest and most severe retinal dystrophy. It occurs as non-syndromic or syndromic. 26/37 LCA genes are important to ciliary function and account for < 1/3 of cases. These cases develop- or are at risk to develop- skeletal, renal and/or neurologic symptoms. Here, we assessed efficiency of ciliome resequencing (CR) as a tool for molecular diagnosis and patient care.
Patients and methods
The DNA of 60 unrelated young children with LCA was screened for mutations using a custom 5.3 Mb Agilent SureSelect Target Enrichment library which captures 32,146 exons of 1,666 genes selected form cilia databases. Segregation analysis of rare candidate variants was performed by Sanger sequencing.
Biallelic disease-causing mutations in known genes were identified in 17/60 patients (30 %): CEP290 (n = 4), CRB1 (n = 4), RPGRIP1 (n = 2), LCA5 (n = 1), IQCB1 (n = 2), IFT140 (n = 2), AHI1 (n = 1), ALMS1 (n = 1). In addition, 3/60 patients harbored biallelic mutations in three novel genes which screening in additional non syndromic and syndromic LCA cases allowed identifying additional mutations in 2/3 of them.
The identification of mutations in known and novel genes in 33 % of the cases, makes targeted sequencing an interesting alternative to exome resequencing. The identification of mutations in several genes responsible for syndromic LCA in young children with no overt extraocular expression demonstrates the importance of NGS-based molecular diagnosis to set-up a rational and efficient follow-up of patients.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.