Centre for Human Genetics, University of Leuven.
In the present paper we report two pairs of slightly 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. (1984) in 4 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.