[3M syndrome: case history]

This case report shall draw attention to a still little known syndrome of primordial nanism. It is important for the differential diagnosis on the genetic counselling, specially with regard to the Silver-Russell syndrome.

A striking mentally retarded (I. Q. 54) 9-year-old boy with primordial proportionate short stature exhibited characteristic features of the 3M syndrome (MMM): pseudohydrocephalic dolichocephalia, short neck with protruding muscles, transversal furrow in the lower thorax, muscular hypotonia with joint laxity - "falling hands", radiographic manifestations included the tall vertebral bodies and gracile long bones. Furthermore there was a dent temporal at the left. But this feature is found on many other syndromes with nanosomia frontotemporal, less frequent the low position of the navel on these patients. The karyotype was normal, the case apparently sporadic.

MMM can be differentiated from other types of nanosomia by clinical criterias; a molecular genetic proof is not yet possible.