Copy number variants (CNVs) are frequent and widespread in the human genome and alter dosage of genes important in conditions ranging from HIV susceptibility to autism spectrum disorders (ASDs). Thus, CNVs are potential diagnostic tools for clinical conditions having a genetic component.

One challenge to applying CNVs to clinical diagnosis is that several small studies have identified differences in the frequency of a given CNV among different racial/ethnic populations, implying that a CNV might be responsible for different disease risk in individuals of different ancestry. Thus, a comprehensive catalog of these variants and their frequencies in non-European populations is a crucial prerequisite for applying CNVs to clinical diagnosis in these populations. One of our projects is to build such a catalog.

Our second project is to use CNVs to study the genetics of the ASDs, a related set of disorders characterized by social and communication problems and repetitive behaviors. These are diagnosed in approximately 0.5% of children in the US and are, therefore, a significant public health concern. Several CNVs have been identified that are associated with increased ASD risk. Such CNVs can be used for diagnosis, for example, to discriminate among the different classifications within the autism spectrum, and to identify the causative genes within the CNV regions. As the CNVs associated with ASDs thus far account for a small part of ASD genetic risk and few candidate genes have been robustly tested, we aim to identify new CNVs and test candidate genes within CNV regions.