Abstract
Microdeletion of chromosome 22q11 is one of the common chromosomal abnormalities associated with inborncardiac defects. The frequency of this microdeletion syndrome is very high.
Its phenotype is associated with veryserious feature (cardiac defects, in certain cases thymic aplasia, immunodeficiency, hypocalcemia, hypoparathy-roidism and cleft palate). The FISH (fluorescent in situ hybridization) method ensures reliable detection ofmicrodeletion 22q11.
According to results of our molecular cytogenetic studies microdeletion 22q11 was detectedroughly in 30 % of patients with inborn cardiac defects and some other phenotypic signs. Most frequent cardiacdefects associated with 22q11 microdeletion are tetralogy of Fallot and interrupted aortic arch.
In two cases otherchromosomal aberrations were found - mosaics 45,X/46,XY and 45,X/46,XX/47,Xder(X).