VARIABLE PHENOTYPES IN VELOCARDIOFACIAL SYNDROME WITH CHROMOSOMAL DELETION

Velocardiofacial syndrome (VCF) has overlapping features with DiGeorge sequence; both result from a developmental field defect oad probably represent contiguous gene deletion syndromes. The association of chromosome 22q11 deletion with DiGeorge sequence led us to do molecular analysis of chromosome 22 in 18 patients with VCF, who ranged in age from 6 to 42 years. All 18 patients had monosomy for the chromosome region 22q11. Retrospectively, we correlated the presence of the deletion with various clinical findings: 100% had cleft palate, 67% the facial phenotype, 83% cardiac disease, 94% learning disabilities, 70% ophthalmologic findings, 50% short stature, 22% psychiatric disorders, and 17% hypocalcemia. Both severely phenotypically affected and mildly affected patients hod the deletion. These findings stress the importance of continued surveillance of all patients with VCF for the many medical problems that may not be present at initial diagnosis. We conclude that the presence of the gene deletion does not predict the phenotypic expression in VCF. Further studies to characterize the size of the gene deletion may facilitate better prediction of the phenotype.