A Novel Microdeletion of 517 kb Downstream of the PAX6 Gene in a Chinese Family with Congenital Aniridia

Overview

Journal BMC Ophthalmol

Publisher Biomed Central

Specialty Ophthalmology

Date 2023 Sep 26

PMID 37752489

Authors

Yinwen Li

Jieqiong Chen

Ying Zheng

Zhixuan Chen

Tao Wang

Qian Sun

Xiaoling Wan

Haiyun Liu

Xiaodong Sun

Affiliations

Soon will be listed here.

Abstract

Background: To identify the disease-causing gene in a Chinese family affected with congenital aniridia.

Methods: Patients underwent systematic ophthalmic examinations such as anterior segment photography, fundus photography, optical coherence tomography, and fundus fluorescein angiography. The proband was screened for pathogenic variants by whole exome sequencing (WES) and copy number variant (CNV) analysis. Real-time quantitative PCR (RT-qPCR) was applied to confirm the CNV results. Breakpoints were identified by long-range PCR followed by Sanger sequencing.

Results: All seven members of this Chinese family, including four patients and three normal individuals, were recruited for this study. All patients showed bilateral congenital aniridia with nystagmus, except the son of the proband, who presented with bilateral partial coloboma of the iris. A novel heterozygous deletion (chr11:31,139,019-31,655,997) containing the 3' regulatory enhancers of the PAX6 gene was detected in this family. We also reviewed the reported microdeletions downstream of PAX6 in patients with aniridia.

Conclusions: We identified a novel microdeletion, 517 kb in size located about 133 kb downstream of the PAX6 gene, responsible for congenital aniridia in this Chinese family, which expands the spectrum of aniridia-associated mutations in PAX6.

Citing Articles

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