Familial Nature of Reading Disability

Abstract

SummaryAn extensive psychometric test battery was administered to 125 children with a reading disability, to their parents and siblings, and to members of 125 matched control families (N = 1,044). In addition to expected differences in spelling and reading, probands obtained significantly (P ≤ · 01) lower scores than controls on tests of other cognitive abilities. Manifold deficits were also found in siblings and parents of probands, conclusively demonstrating the familial (genetic and/or common-family environmental) nature of the disorder.