Microsatellite DNA markers detects 95% of chromosome 22q11 deletions.
Cono-truncal cardiac malformations account for some 50% of congenital heart defects in newborn infants. Recently, hemizygosity for chromosome 22q11.2 was reported in patients with the DiGeorge/Velo-cardio-facial syndromes (DGS/VCFS) and causally related disorders. We have explored the potential use of microsatellite DNA markers for rapid detection of 22q11 deletions in 19 newborn infants referred for cono-truncal heart malformations with associated DGS/VCFS anomalies. A failure of parental inheritance was documented in 84.2% of cases (16/19). PCR-based genotyping using microsatellite DNA markers located within the commonly deleted region allowed us either to confirm or reject a 22q11 microdeletion in 94.3% of cases (18/19) within 24 hours. This test is now currently performed in the infants referred to us for a cono-truncal heart malformation as a first intention screening for 22q11 microdeletion.
Bonnet
D
D
Unité de Recherches sur les Handicaps Génétiques de l'Enfant-INSERM U-393, Hôpital des Enfants Malades, Paris, France.
Cormier-Daire
V
V
Kachaner
J
J
Szezepanski
I
I
Souillard
P
P
Sidi
D
D
Munnich
A
A
Lyonnet
S
S
D000483:Alleles; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics*; D004062:DiGeorge Syndrome / Q000175:diagnosis* / Q000235:genetics*; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000235:genetics; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007231:Infant, Newborn; D018895:Microsatellite Repeats; D010375:Pedigree; D016133:Polymerase Chain Reaction; D017384:Sequence Deletion