Pericentric enversion of chromosome no. 13 in a large family leading to duplication deficiency causing congenital malformations in three individuals.

Received 4 April 1972. * Cytogenetics Laboratory, Genetics Committee of the University of Iceland, Department of Pathology, Reykjavik, Iceland. t Paediatric Department, University Hospital Iceland; Home for the Mentally Retarded, K6pavogur; Paediatric Department, St Joseph's Hospital, Reykiavik, Iceland. t John F. Kennedy Instituttet, GI. Landevej 7-9, Copenhagen, Denmark. ** Faculty of Medicine, University of Calgary, Calgary 42, Alberta, Canada. duplication deficiency derived from a maternal Dgroup pericentric inversion. A female with secondary amenorrhoea, webbed neck, and kyphosis and a chromosome D pericentric inversion was reported by Cohen, Capraro, and Takagi (1966/1967). Crandall and Sparkes (1970) described a pericentric inversion in 9 members of a family, all of whom were phenotypically normal. In the family presented here (Fig. 1) 3 children had congenital malformations. Chromosome analysis could only be performed in 2 of them, both had abnormal karyotypes. Chromosome studies in the family showed that 14 phenotypically normal individuals had an abnormal karyotype which differed from that found in the 2 abnormal children.