X-linked mental retardation with marfanoid habitus.

Here we report on two pairs of mildly to moderately mentally retarded brothers with marfanoid habitus and similar craniofacial changes. They had a long and narrow face, small mandible, high-arched palate, and hypernasal voice, as previously reported by Lujan et al (Am J Med Genet 17:311-322, 1984) in four mentally retarded males of a large kindred. The present data suggest the existence of a specific type of X-linked mental retardation with marfanoid habitus.