Genetic tool used to diagnose achromatopsia: first case report from India

Abstract

Abstract Background Achromatopsia is an autosomal recessive disease characterized by poor visual acuity, lack of color vision, nystagmus, and marked photophobia. The symptoms can be extremely disabling, and at present, there is no cure available. Mutations in the CNGA3, CNGB3, GNAT2, PDE6C, PDE6H, and ATF6 genes have been identified as associated with this disease. The genetic approach for these patients is currently an important issue, and gene therapy is an ongoing therapeutic option already being studied in clinical trials. Case presentation We report the case of two siblings (8 and 5 years old) affected by achromatopsia. They carry compound heterozygous mutations in the CNGA3 gene at positions 1306 and 1279 in exon 8 (c.1306C > T, p.Arg436Trp and c.1279C > T, p.Arg427Cys). The parents were found to have one of the variants in a heterozygous condition. This is the first reported case of achromatopsia in India. Conclusion This report emphasizes the importance of genetic testing in such patients, which can aid not only in the diagnosis and management but also in providing counseling to parents regarding the significance of prenatal diagnosis in future pregnancies, helping them make informed choices. Due to its variable presentation, the diagnosis of achromatopsia may be challenging, and exome sequencing has proven to be a crucial diagnostic tool.

Keywords

• Exome sequencing
• Achromatopsia
• Genetic testing
• Compound heterozygous
• Prenatal diagnosis