3-Methylglutaconic Aciduria, Type III (OPA3)
3-methylglutaconic aciduria, type III is an autosomal recessive disease caused by pathogenic variants in the gene OPA3. Although patients of different ethnicities have been reported, this disease is more prevalent in Sephardic Jewish populations from Iran. Clinical features include early-onset bilateral optic atrophy which leads to decreased vision and mild to moderate intellectual disability. With increasing age, most patients develop ataxia, spasticity, or other movement disorders. Life expectancy is not thought to be decreased, and no genotype-phenotype correlation has been noted.
For information about carrier frequency and residual risk, please see the residual risk table.