Beginning in the late 1990’s when individuals with a deletion of the chromosome 22q11.2 region were noted to have an increased risk for neuropsychiatric conditions, numerous studies have focused on elucidating this association. Around the end of the first decade of the present century, multinational investigators realized that bringing together their data on the neuropsychiatric phenotype observed in individuals with the 22q11.2 deletion would substantially increase the statistical power to detect meaningful genotype-phenotype association signals. Towards this end, the International 22q11DS Brain Behavior Consortium (IBBC) was formed. The consortium, funded by the US National Institute of Mental Health (NIMH1), brought together investigators from 22 clinical and 5 genomic sites across the world with the objective to identify genetic variation associated with the neuropsychiatric phenotypes expressed in this condition. An additional objective was to increase insight into the spectrum of neuropsychiatric disorders, both from a categorical and from a dimensional perspective. An important question in this regard was to examine possible early behavioral and or cognitive changes preceding the onset of schizophrenia in this population. A more extensive discussion of history and objectives of the IBBC, can be found here.


The core dataset generated by the IBBC consists of whole genome SNP array data and whole genome sequencing data, and quality controlled phenotypic data including schizophrenia spectrum disorders and cognitive (IQ) data, as well as additional neurodevelopmental and other psychiatric phenotypes (ADHD, ASD, mood and anxiety disorders). A comprehensive report on the full range of psychopathology observed in over 1,400 individuals with 22q11DS, the largest cohort ever described, can be found here. The IBBC data are available through the National Institute of Mental Health Data Archive repository.