Brief clinical report: an X-linked mental retardation syndrome with craniofacial abnormalities, microcephaly and club foot.

A male infant, who died of renal insufficiency at 6 months, had 2 similarly affected maternal uncles who died at 16 and 6 months respectively. Their manifestations include microcephaly, a large anterior fontanel, short nose with anteverted nostrils, club foot deformity, retarded psychomotor development and, in the index case only, kidney hypoplasia and dysplasia. The 2 obligatory carriers of this evidently X-linked recessive syndrome had no physical abnormalities.