[Partial trisomy 10p in combination with partial monosomy 20p--a syndrome with muscular hypotonia, psychomotor retardation, dwarfism and craniofacial dysmorphia].

The clinical syndrome resulting from deletion of 20p in combination with duplication of 10p, seen in two male members of the same family, is reported for the first time. The sister of one and the mother of the other patient are asymptomatic carriers of a balanced translocation. The two patients have multiple stigmata including dwarfism and pronounced psychomotoric retardation. The syndrome corresponds largely to an addition of the symptoms seen in cases with deletion of 20p and duplication of 10p reported hitherto.