Abstract
Purpose :
High myopia (HM) is generally considered as a complex trait determined by both environmental and genetic factors. Based on previous studies of high myopic pedigrees and sporadic cases, six genes have been discovered as replicable disease-causing genes of non-syndromic HM, including ZNF644, SCO2, CCDC111, LRPAP1, SLC39A5 and LEPREL1. The purpose of our study is to achieve a clear picture of mutational spectrum in a large cohort of Chinese patients with non-syndromic HM, and to reveal the genotype-phenotype correlation.
Methods :
Clinical data and genomic DNA were collected from 540 Chinese patients with non-syndromic HM. Mutational screening were performed on all coding sequences and intron/exon junctions. Finally, we assessed the clinical relevance of identified mutations, under the guidance of ACMG.
Results :
The phenotypic severities of the different affected patients were classified into five stages, based on their refractive errors, axial lengths, and fundus manifestations. Thirty-eight index cases were confirmed to harbor mutations in the known pathogenic genes, among them there were fifteen novel mutations. Thereinto, SLC39A5 accounts for the largest proportion with a mean mutation rate of 2.3% (13/540, 2.3%), followed by ZNF644 (12/540, 2.2%), CCDC111 (7/540, 1.3%), SCO2 (5/540, 0.9%), and LRPAP1 (1/540, 0.2%). No homozygous or compound heterozygous variants were found in LEPREL1.
Conclusions :
We uncovered an expanding genetic landscape and phenotypic spectrum through the study of 540 Chinese patients with non-syndromic HM. A biological link was firstly established between the genetic deficiency and phenotypic traits. To our best knowledge, it is hereunto the largest cohort with HM that have ever been studied.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.