An overview of correlations between schizophrenia and 22q11.2 deletion syndrome

Objective: 22q11.2 deletion syndrome (22q11DS) is a genetic syndrome associated with a microdeletion of the chromosome 22 band q11 with an estimated prevalence of between 1:2,500 and 1:4,000 live births. Studies of school-age children have shown that individuals with 22q11DS have very high rates of psychiatric morbidity and abnormal behaviors. By late adolescence and early adulthood, up to one-third of patients with 22q11DS develop psychotic disorders resembling above all schizophrenia and schizoaffective disorder. Therefore, 22q11DS is of considerable interest to research concerned with the genetic and epigenetic mechanisms involved in the development of schizophrenic disorder. Method: A comprehensive literature review based on PubMed/MEDLINE, Cochrane Library, Cinhal and PsycInfo was undertaken. Results: Schizophrenic disorder associated with 22q11DS largely resembles that found in the general population as regards the core signs and symptoms, treatment response, neurocognitive profle and MRI brain anomalies. Conclusions: Individuals with 22q11DS are an easy identifable high-risk group for schizophrenia whose transition rate in early adulthood may be as high as 30%, regardless of environmental factors. This syndrome is thus of considerable interest to researchers and clinicians involved in the early intervention/prevention of schizophrenia.