The deletions of 22q11--the Portuguese experience

Abstract

The patients with a chromosome 22q11 deletion have a variable phenotype which includes DiGeorge (DG) and Velocardiofacial (VCF) syndromes. The aim of the present study is to characterize the phenotype of DG and VCF using facial biometry in 12 portuguese patients. We found 4/12 patients with the DG phenotype: 3/4 had telecanthus, small mouth and retrognathia; 1/4 had telecanthus, short nose with bulbous tip and a normal mouth. These patients had major cardiac defects associated with hypoplastic or absent thymus and monosomy 22q11. We did not find velopharyngeal insufficiency in patients with the so called DG phenotype 8/12 patients had the VCF phenotype: typical facies with variable features. Four of these had velopharyngeal insufficiency and learning disabilities. Four patients had cardiac defects and 5/8 had monosomy 22q11. Probably this clinical variability is due to mutations in critical genes involved in embryonic development.