To investigate molecular genetic characteristics of CATCH 22 syndrome, we studied the correlation between phenotype and target gene screening and mode of inheritance using FISH (fluroscence in situ hybridization) and STRP(short tandem-repeated polymor...
To investigate molecular genetic characteristics of CATCH 22 syndrome, we studied the correlation between phenotype and target gene screening and mode of inheritance using FISH (fluroscence in situ hybridization) and STRP(short tandem-repeated polymorphism). Hemizygosity for a region of 22q11.2 was found in 21 CATCH 22 patients. 2 of 19 family (11%) had familial CATCH 22 syndrome and affected 2 parents were mothers. No familial cases were found among CATCH 22 syndrome with absent thymus/ DiGeorge syndrome. The conotruncai cardiac anomalies such as Tetralogy of Fallot and vascular anomalies were common among CATCH 22 syndrome. Both the STRP maker screening(D22S941) and FISH(D22S75) were efficient and useful for the detection of chromosome 22q11 deletion and the evaluation of parent of origin but show some heterogeniety. Markers D22S75 and D22S941 appear to be consistently hemizygous in patients with deletions, so it was very useful in screening the patients with the conotrucal cardiac anomalies.