Novel gene mutation and clinical features in a family with gyrate atrophy of choroid and retina

Abstract

AIM: To investigate the pathogenic mutations of the OAT gene in a Chinese family affected with gyrate atrophy of choroid and retina(GA)and describe their clinical manifestations.METHODS: All available family members have underwent detailed ophthalmological examinations. The sequencing results and pathogenic mutations were clarified by whole exome sequencing, bioinformatics analysis and Sanger sequencing.RESULTS: Based on the clinical manifestations and symptoms, the proband was diagnosed with GA. A missense mutation of c.722C>T(p.P241L)in exon 6 and a nonsense mutation of c.1186C>T(p.R396X)in exon 10 were identified in the OAT gene of the proband, which was a compound heterozygotic mutation. This compound heterozygous mutation showed co-segregation in the family. The heterozygous pathogenic variant of p.R396X was detected in both the proband's father and elder brother, and the heterozygous pathogenic variant of p.P241L was detected in proband's mother. Except for the proband, no other family members have abnormal clinical manifestations.CONCLUSION: The proband of this family is a compound heterozygous mutation, in which p.P241L is the first reported gene mutation type. This result expands the range of OAT gene variation and is conducive to further understanding the pathogenic factors of GA at the molecular basis level. The discovery and confirmation of the novel mutation type will also help to provide a new basis for the clinical diagnosis and gene therapy of GA.

Keywords

• gyrate atrophy of choroid and retina
• macular retinoschisis
• macular edema
• ornithine aminotransferase
• whole exome sequencing
• genetic variation