Typical phenotypic spectrum of velocardiofacial syndrome occurs independently of deletion size in chromosome 22q11.2.
Velocardiofacial syndrome (VCFS) is a relatively common developmental disorder characterized by craniofacial anomalies and conotruncal heart defects. Many VCFS patients present hemizygous deletions on part of chromosome 22q11.2; suggestive that haploinsufficiency in this region is responsible for this etiology. Most 22q11.2 deletions occur sporadically, although in some cases the deletion may be transmitted. A total of 29 VCFS patients and their parents were genotyped using six consecutive polymorphic markers (STS) of the chromosome 22q11.2: D22S420, D22S941, D22S264, D22S306, D22S425, and D22S257. The results revealed that 72% (21/29) of the patients harbored a deletion involving the polymorphic markers D22S420, D22S941, and/or D22S264. Haplotype analysis showed that among the patients studied, the deletions were either of maternal or paternal origin. Our findings demonstrated that independently of their size, any deletion occurring in the VCFS critical region is enough to confer the patient phenotype.
Sandrin-Garcia
Paula
P
Molecular Immunogenetics Group, Department of Genetics, Faculty of Medicine of Ribeirão Preto, University of São Paulo (USP), Ribeirao Preto, SP, Brazil.
Abramides
Dagma V M
DV
Martelli
Lúcia R
LR
Ramos
Ester S
ES
Richieri-Costa
Antônio
A
Passos
Geraldo A S
GA
D000015:Abnormalities, Multiple; D000293:Adolescent; D002648:Child; D002872:Chromosome Deletion; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics*; D019465:Craniofacial Abnormalities / Q000235:genetics; D004247:DNA / Q000032:analysis; D004062:DiGeorge Syndrome / Q000235:genetics*; D005260:Female; D005819:Genetic Markers; D005838:Genotype; D006801:Humans; D008297:Male; D010375:Pedigree; D010641:Phenotype; D016133:Polymerase Chain Reaction
D005819:Genetic Markers; D004247:DNA