Deletion of the 16p11.2 chromosomal region is one of the most common causes of autism spectrum disorders (ASD) and developmental delay. Individuals with 16p11.2 deletion syndrome present with intellectual disability, language impairments, social deficits and motor delays. Interestingly, the magnitude of these deficits varies substantially from one individual to another. This makes the 16p11.2 deletion carrier population especially important for understanding the complex origins of the symptoms associated with ASD and other neurodevelopmental disorders.

The Simons Variation in Individuals Project (Simons VIP) has clinical and neuroimaging data for 16p11.2 deletion carriers, which allows for initial analyses of genotype-phenotype relations. However, there is no comprehensive cognitive and neurobehavioral profile for these individuals. Such a profile is key to characterizing the various ASD subtypes and understanding their underlying neurobehavioral deficits.

Mor Nahum and her colleagues at Posit Science have recently developed a comprehensive, web-based cognitive battery to assess perceptual and cognitive abilities in children and adults. This battery is particularly appealing for use in the 16p11.2 deletion population. The difficulty level of the assessments is adaptively varied to allow for performance measurement of lower-functioning individuals, and the battery is administered entirely online, using secure online data registration, allowing individuals located virtually anywhere to complete them.

In this project, Nahum and her colleagues plan to use this battery to obtain a comprehensive cognitive profile of 16p11.2 deletion carriers and matched controls. These cognitive profiles will allow the researchers to tap into specific functional difficulties in each tested domain and document correlations in performance difficulties between and within brain function domains. Furthermore, the team plans to look at specific correlations between these cognitive profiles and the existing clinical and neuroimaging data already collected for the 16p11.2 individuals as part of Simons VIP. This will allow the researchers to answer questions regarding the true nature of the deficits expressed in severely affected carriers, and to tease apart the factors that underlie core deficits in the 16p11.2 population. Results from this study are expected to provide new insight into how copy number variants lead to the complex expressions of ASD and related neurobehavioral disorders.