Classical Noonan syndrome is not associated with deletions of 22q11.
Deletions of 22q11 cause DiGeorge sequence (DGS), velo-cardio-facial syndrome (VCFS), conotruncal anomaly face syndrome, and some isolated conotruncal heart anomalies. Demonstration of a 22q11 deletion in a patient with manifestations of DGS and Noonan syndrome (NS) has raised the question of whether NS is another of the chromosome 22 microdeletion syndromes. This prompted us to evaluate a cohort of patients with NS for evidence of 22q11 deletions. Five of 6 NS propositi studied in our laboratory with marker N25 (D22S75) did not have a 22q11 deletion. A 2-month-old infant with several findings suggestive of NS did have a 22q11 deletion, suggesting that a small number of 22q11 deletion propositi may present with a NS-like picture. However, most cases of NS must have another cause.
Robin
N H
NH
Department of Pediatrics, Children's Hospital of Philadelphia, PA 19104, USA.
Sellinger
B
B
McDonald-McGinn
D
D
Zackai
E H
EH
Emanuel
B S
BS
Driscoll
D A
DA
D000293:Adolescent; D002675:Child, Preschool; D002872:Chromosome Deletion; D002892:Chromosomes, Human, Pair 22; D015331:Cohort Studies; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009634:Noonan Syndrome / Q000235:genetics*