Noonan ' s and DiGeorge syndromes with monosomy 22 q

A boy with the dysmorphic features of Noonan's syndrome and pulmonary valve stenosis who had evidence of hypoparathyroidism and abnormal T lymphocyte numbers in the neonatal period is reported. He had a normal karyotype but molecular analysis revealed a submicroscopic deletion within chromosome 22qll, the region deleted in DiGeorge syndrome. Thus this child has both Noonan's syndrome and DiGeorge syndrome; 22qll is a candidate region for a gene defective in Noonan's syndrome. (Arch Dis Child 1993;68:187-9) Department of Human Genetics, 19 Claremont Place, Newcastle upon Tyne NE2 4AA D I Wilson I E Cross Good Hope General Hospital, Sutton Coldfield, West Midlands S Bennett Britton West Midlands Genetic Semces, Bingm Maternity Hospital C McKeown Department of Biochemistry and Molcular Genetics, St Mary's Hospital Medical School, London D Kelly P J Scambler Department of Immunolog, Institute of CNild Health, London S Strobel