Syndrome associated with a deficiency of part of the long arm of chromosome no. 18.

In 1964 de Grouchy, Royer, Salmon, and Lamy described a deaf and mentally retarded microcephalic girl in whom the long arm of one No. 18 chromosome was about half its usual length. Since then two other microcephalic children, a boy and a girl, have been found to have this chromosome aberration (Lejeune, Berger, Lafourcade, and R6thore, 1966). Lejeune suggested on the basis of their findings that a recognizable syndrome was emerging in association with this deficiency. This paper presents the clinical features and results of the genetic investigations of two further cases, both boys, in whom the tetrad of microcephaly, minute penis, cryptorchidism, and talipes equinovarus was present.