Macrocephaly and mental retardation. The unique association with short stature, spastic paraplegia and CNS malformations.

During a systematic clinical genetic survey of the institutionalized moderately to severely mentally retarded we had the occasion to examine two nonrelated adult patients who presented a similar MCA/MR syndrome: 1) macrocephaly (OFC > 60 cm) with high and broad forehead and contrasting relative midfacial hypoplasia; 2) short stature with small and broad hands and feet; 3) neurological symptoms of a variable degree of spastic paraplegia and severe CNS malformations on CT-scan i.e. internal hydrocephalus and Dandy-Walker variant malformation.