Dominant Optic Atrophy With Varied Phenotype in a Family of Eastern India: A Case Report of a Rare Mutation

Abstract

Autosomal dominant optic atrophy (ADOA) can present with a varied phenotype in the form of pure ADOA, ADOA with sensorineural hearing loss, or the extended spectrum of DOA plus syndrome. Multiple genes have been identified over the years and majority of the cases are attributed to OPA1 gene mutation. Here we present an index case of DOA plus syndrome with affection of multiple family members across 2 generations with a rare mutation detection. A middle-aged female presented with onset of bilateral progressive visual blurring in the first decade followed by progressive sensorineural hearing loss since the second decade and onset of lower limb predominant cerebellar ataxia since the third decade. Routine parameters, imaging and electrophysiological studies were negative. Next generation clinical exome sequencing (NGCES) revealed an unique OPA1 gene mutation with worldwide evidence of only 3 such cases in database. DOA suspicion should be made in early onset visual defects with multiaxial involvement with a significant family history.