Genetics and Psychopathology in the 22q11 Deletion Syndrome

The study of genes that are implicated in various mental diseases is increasingly relevant. The association between a gene and a disease can provide valuable information on how the neurobiology of the brain is altered, by studying the function of the protein encoded by the gene. This information is important for the development of new treatments.

However, the identification of these "disease" genes is difficult, due to the complexity of human behavior and the interaction of multiple genes. Moreover, the human genome consists of approximately 35,000 genes, further complicating the matter.

The situation is simplified when a psychiatric disorder and a genetic anomaly co-occur; assuming a causative relation, one can focus on the implicated genetic region.

The 22q11-deletion syndrome (22q11DS) is an example of this type; this syndrome is caused by a disappearance ("deletion") of 20-30 genes in a well-defined region on chromosome 22. People with 22q11DS have a high risk of autism and psychosis, therefore one or more genes in the 22q11DS region must be associated with these disorders.

In this study we aim to identify these genes, by carefully studying psychiatric symptoms (and additional parameters of brain functioning) in a large sample of 22q11DS children and subsequently statistically correlate these findings to specific genes within the 22q11DS region. If genes associated with autism and/or psychosis in the 22q11DS population can be found, they may help to understand the underlying neurobiology that cause these diseases, not only in 22q11DS patients but in the general population as well.