A novel PAX6 deletion in a Chinese family with congenital aniridia

•A novel deletion mutation c.796 del G (p.A266 fs) within PAX6 gene was identified.•The PAX6 deletion mutation caused nonsense-mediated mRNA decay.•This finding further enriched the aniridia pathogenic mutation spectrum.

Aniridia is a rare, congenital ocular disorder with the characteristics of incomplete formation of the iris caused by the mutations of the paired box gene-6 (PAX6). To investigate the clinical characterization and the underlying genetic defect in a Chinese family with autosomal dominant aniridia, we recruited the family members who underwent comprehensive ophthalmic examination. A novel heterozygous PAX6 deletion mutation c.796 del G (p.A266 fs) (GenBank ID: KP255960) in exon 10 was exclusively observed in all affected individuals but not in any of the unaffected family members or unrelated controls. The PAX6 mRNA level was about 50% lower in patients with aniridia than in unaffected family members, indicating that this mutation caused nonsense-mediated mRNA decay. In conclusion, we identified a novel deletion mutation in the PAX6 gene resulting in an abnormal PAX6 COOH-terminal extension in the Chinese family with aniridia. Our study further expands the mutation spectrum of PAX6.