[Proximal trisomy 19q. Interstitial deletion and ring chromosome derived from 19q].

A proximal 19q duplication was observed in lymphocytes of a young boy with mental retardation, dysmorphism (weight excess, macrocephaly, downward slanted palpebral fissures, hypertelorism, broad nose, typical mouth), without visceral malformation. His mother had an interstitial deletion and ring chromosome derived from 19q.