Ocular manifestations of Chinese patients with copy number variants in the gene.

PURPOSE

Familial exudative vitreoretinopathy (FEVR) and Norrie disease (ND) are genetic disorders that can be caused by mutations in the gene and affect retinal vasculature growth and development. This study aimed to describe the copy number variations (CNVs) in the gene in Chinese FEVR families and the associated phenotypes.

METHODS

This study recruited 651 FEVR families. SeqCNV was used to analyze the CNVs in the families without mutations in known FEVR-associated genes. Multiplex ligation-dependent probe amplification and semiquantitative multiplex PCR were performed to verify the CNVs. The probands and family members underwent complete ocular examinations.

RESULTS

CNVs were identified in four patients from three unrelated families, accounting for 15% of the patients with mutations and 0.46% of the entire FEVR cohort. Exon 2 deletions were detected in two families, and whole gene deletion was identified in one family. The affected individuals were born blind with total retinal detachment.

CONCLUSIONS

The findings confirm that CNVs are a common mutation type. The CNV-associated phenotype is congenital blindness with total retinal detachment. Antenatal genetic analyses and fetal ultrasound can facilitate early diagnosis and interventions in patients with mutations.