Prenatal diagnosis of deletion 17p13 associated with DiGeorge anomaly.

A fetus, subsequently shown to have the deletion 17p13, was detected at 30 weeks' gestation because of multiple anomalies and polyhydramnios on ultrasonography. The fetus died and was born at 34 weeks of gestation. Pathologic examination showed intrauterine growth retardation, double outlet right ventricle (a conotruncal cardiac defect), and thymic hypoplasia suggesting partial DiGeorge anomaly. To our knowledge, DiGeorge anomaly has not been reported previously in conjunction with del(17p) nor in the Miller-Dieker syndrome. Since this deletion is the largest deletion of distal 17p observed so far, one explanation for this association may be the presence of a gene on proximal 17p for neural crest development.