Expanding the genetic spectra of gyrate atrophy of the choroid and retina in a Chinese cohort in Yunnan province.

BACKGROUND: Gyrate atrophy (GACR), a rare autosomal recessive chorioretinal dystrophy caused by OAT mutations, is genetically and clinically underexplored in multi-ethnic Chinese populations. RESULTS: Eight patients from five families all exhibited high myopia (mean - 8.28 D), early-onset vision loss, and elevated plasma ornithine. Parapapillary atrophy (PPA) was common (76.92%) and correlated with worse BCVA and longer AL. Four novel OAT mutations were identified: c.213G > A (p.Trp71Ter), c.799 A > C (p.Thr267Pro), c.897 C > A (p.Tyr299Ter) and c.-30 + 22_-30 + 43del. Minigene assays confirmed aberrant splicing for the latter. CONCLUSIONS: This study identifies the first pathogenic 5' UTR variant in GACR, reveals ethnic-specific mutation profiles, and underscores PPA as a severity-linked feature.