SummaryInherited optic neuropathies are a heterogeneous group of disorders characterized by mild to severe visual loss, colour vision deficit, central or paracentral visual field defects and optic disc pallor. Optic atrophies can be classified into isolated or non-syndromic and syndromic forms. While multiple modes of inheritance have been reported, autosomal dominant optic atrophy and mitochondrial inherited Leber's hereditary optic neuropathy are the most common forms. Optic atrophy type 1, caused by mutations in theOPA1gene is believed to be the most common hereditary optic neuropathy, and most patients inherit a mutation from an affected parent. In this study we used whole-exome sequencing to investigate the genetic aetiology in a patient affected with isolated optic atrophy. Since the proband was the only affected individual in his extended family, and was a product of consanguineous marriage, homozygosity mapping followed by whole-exome sequencing were pursued. Exome results identified a novelde novo OPA1mutation in the proband. We conclude, that thoughde novo OPA1mutations are uncommon, testing of common optic atrophy-associated genes such as mitochondrial mutations andOPA1gene sequencing should be performed first in single individuals presenting with optic neuropathy, even when dominant inheritance is not apparent.
Homozygosity Mapping using Whole-Exome Sequencing: A Valuable Approach for Pathogenic Variant Identification in Genetic Diseases