Simultaneous expression of two pathogenic genes in four Chinese patients affected with inherited retinal dystrophy

Abstract:

AIM: To describe the complex, overlapping phenotype of four Chinese patients with inherited retinal dystrophies (IRDs) who harbored two pathogenic genes simultaneously. METHODS: This retrospective study included 4 patients affected with IRDs. Medical and ophthalmic histories were obtained, and clinical examinations were performed. A specific Hereditary Eye Disease Enrichment Panel (HEDEP) based on exome capture technology was used for genetic screening. RESULTS: Four patients were identified to harbor disease-causing variants in two different genes. Patient retinitis pigmentosa (RP) 01-II:1 exhibited both classical ABCA4 -induced Stargardt disease (STGD) 1 and USH2A-associated RP, patient RP02-III:2 exhibited both classical ABCA4-induced STGD1 and CDH23-associated RP, patient RP03-II:1 exhibited both USH2A-induced autosomal recessive retinitis pigmentosa (arRP) syndrome and SNRNP200-induced autosomal dominant retinitis pigmentosa (adRP), and patient RP04- II:2 exhibited USH2A-induced arRP syndrome and EYS-induced arRP at the same time. CONCLUSION: Our study demonstrates that genotype–phenotype correlations and comprehensive genetic screening is crucial for diagnosing IRDs and helping family planning for patients suffering from the disease.

Key words:inherited retinal dystrophies; Hereditary Eye Disease Enrichment Panel; retinitis pigmentosa; Stargardt disease; two pathogenic genes