A severely retarded 18-year-old boy with tertiary partial trisomy 14.

An 18-year-old severely mentally and physically retarded boy was found to have an unbalanced chromosome complement 47,XY, + 14q-. He had the characteristic facial dysmorphis, abnormal hands, and other features described previously in cases of partial trisomy 14, but appears to be the oldest case reported. His mother is a reciprocal translocation carrier, and lack of other carriers in the family is noteworthy.