UNIPARENTAL ISODISOMY FOR CHROMOSOME-16 IN A GROWTH-RETARDED INFANT WITH CONGENITAL HEART-DISEASE

We report a growth-retarded infant with congenital heart disease and m aternal isodisomy for chromosome 16. Non-mosaic trisomy 16 was detecte d at mid-trimester chorionic villus sampling, performed because bioche mical screening indicated an increased Down's syndrome risk. Further k aryotyping analysis of the placenta, after delivery, showed a 50 per c ent mosaic trisomy 16. The infant had an atrioventricular (A-V) canal defect, scoliosis, and several minor dysmorphic features. Although uni parental disomy for chromosome 16 has been reported previously, to our knowledge this is the first case of uniparental isodisomy for chromos ome 16 which has been investigated with multiple DNA probes.