Autism can be caused by a number of different genetic alterations, some of which result in known syndromes. In 2011, a genetic study of a large sample of children in the Simons Simplex Collection, a database of genetic and clinical information from families that include one child with autism, showed a strong association between duplication of the Williams syndrome chromosomal region (7q11.23) and autism.
Since 2005, when 7q11.23 duplication syndrome was first identified, studies of the syndrome have been limited almost entirely to case studies of individual children. Carolyn Mervis and her colleagues plan to comprehensively examine the behavioral characteristics of 60 individuals with 7q11.23 duplication syndrome, aged 4 to 17 years, in order to understand how this duplication contributes to the genetic underpinnings of autism spectrum disorders. The research team for this study includes developmental and child clinical psychologists, a speech-language pathologist, a clinical geneticist and a molecular geneticist.
The study involves extensive assessments to characterize each child’s behavior with regard to the core domains affected by autism: reciprocal social interaction, verbal and nonverbal communication, and repetitive behaviors and restricted interests (including sensory modulation difficulties). The researchers plan to assess characteristics such as intellectual ability, adaptive behavior and reading and mathematics achievement, as well as test for motor speech disorders, anxiety, attention deficit hyperactivity disorder and other neurological disorders.
This study will provide the first systematic description of the behavioral characteristics of children with 7q11.23 duplication syndrome. Mervis’s findings should be particularly useful in combination with the results of another Simons Foundation Autism Research Initiative project examining the characteristics of a 7q11.23 duplication mouse model, directed by Lucy Osborne at the University of Toronto. Together, these projects could offer a strong foundation for research designed to illuminate genetic pathways that lead to core and associated features of autism spectrum disorders.