OBJECTIVE:To review historical, epidemiological, clinical, etiological and laboratorial aspects of the 22q11.2 deletion syndrome, highlighting the importance of the diagnosis and its difficulties. DATA SOURCES: MedLine, Lilacs e SciELO databases, as well as internet and book chapters written in English, were searched for the period of 1980-2008, with the following descriptors "22q11", "DiGeorge", "Velocardiofacial" and "CATCH22". DATA SYNTHESIS: 22q11.2 deletion syndrome, also known as DiGeorge or velocardiofacial syndrome, was identified in the beginning of the 1990 decade. The 22q11.2 microdeletion is one of the most common human genetic microdeletion syndromes. It is characterized by a very broad phenotypic spectrum. More than 180 physical and behavioral clinical findings have already been described. However, none of them is characteristic or essential to diagnosis. The majority of the patients present a small deletion only detected by molecular genetic techniques as the fluorescent in situ hybridization. The deletion segregates in the families with an autosomal dominant pattern of inheritance, so the recurrence risk in the families is 50%. CONCLUSIONS: Individuals with 22q11.2 deletion syndrome have a great possibility to undergo medical interventions and hospitalizations throughout their lives. Early diagnosis is essential for the evaluation and clinical management of the patients and their families.
velocardiofacial syndrome; DiGeorge syndrome; human chromosomes; in situ hybridization; genetic counseling
