Clinical heterogeneity in autosomal dominant optic atrophy in two 3q28-qter linked central Illinois families

Purpose: To examine the clinical and genetic heterogeneity of autosomal dom inant optic atrophy among two unrelated central Illinois families. Methods: Forty-three individuals from two pedigrees had complete eye examinations. Linkage analysis was performed with microsatellite markers from the region 3q28-29. Results: Visual acuity in 21 affected individuals ranged from 20/2 5 to 20/800. Vision loss was more severe in males than females (P = 0.02). Color vision testing revealed generalized dyschromatopsia. Both visual acui ty and color vision deteriorated with age. Linkage was established to chrom osome 3q28-29 (LODmax = 4.68 for D3S2305). Conclusion: Autosomal dominant o ptic atrophy linked to chromosome 3q28-29 shows intrafamilial phenotypic va riation as well as sex-influenced severity in two Midwestern families.