A rare case of interstitial del(1)(p34.3p36.11) diagnosed prenatally.

We report a very rare constitutional interstitial deletion of chromosome 1p defined within 1p34.3-36.11 bands with an intact pter. The diagnosis was made by standard cytogenetics and fluorescence in situ hybridization (FISH) studies on a cordocentesis specimen obtained at 21 weeks gestation. Termination of pregnancy was performed at 22 weeks gestation due to the ultrasound diagnosis of congenital heart disease. Autopsy confirmed congenital heart disease (cardiomegaly, Ebstein's anomaly, secundum atrial septal defect, subendocardial fibroelastosis), pulmonary lymphangiectasis, a high arched palate, short neck, and bilateral long proximally implanted thumbs. To our knowledge, this is the first case of del(1) (p34.3p36.11) diagnosed prenatally.