Study finds new ADHD genes, links susceptibility with autism and other neuropsychiatric conditions

Study finds new ADHD genes, links susceptibility with autism and other neuropsychiatric conditions

New research led by The Hospital for Sick Children (SickKids) and the University of Toronto has identified more genes in attention deficit hyperactivity disorder (ADHD) and shows that there is an overlap between some of these genes and those found in other neuropsychiatric conditions such as autism spectrum disorder (ASD). The scientists used microarrays (gene-chip technology) to study the DNA of 248 unrelated patients with ADHD. They specifically searched for copy number variants (CNVs), which are insertions or deletions affecting the genes. In three of 173 children for whom the DNA of both parents was available, they found spontaneous CNVs, which occur when the parents are not affected and mutations are new to the child. Rare CNVs that were inherited from affected parents were found in 19 of 248 patients.

Within the group of inherited CNVs, the researchers found some of the genes that had previously been identified in other neuropsychiatric conditions including ASD. To explore this overlap, they tested a different group for CNVs. They found that nine of the 349 children in the study, all of whom had previously been diagnosed with ASD, carried CNVs that are related to ADHD and other disorders. The findings suggest that some CNVs, which play a causal role in ADHD, demonstrate common susceptibility genes in ADHD, ASD and other neuropsychiatric disorders.

"For the first time, we've tested these genetic alterations in ADHD and have a pretty good handle on a couple of decent ADHD candidate genes," says Scherer, who is also Professor in the Department of Molecular Genetics at the University of Toronto and GlaxoSmithKline Chair in Genome Sciences at SickKids. "This is critical, as it gives us confidence in interpreting our results."

ADHD is a common neuropsychiatric disorder that affects four per cent of school-age children worldwide. It is associated with inattention, hyperactivity and impulsiveness that often results in learning difficulties, social problems and underachievement. ASDs are diagnosed in roughly one in 100 children in North America and cause deficits in communication, social understanding and behaviour.

For more information on this study visit the above webpage. For information on services for children, adolescents and adults with autism spectrum disorder (ASD) please visit my website at http://www.relatedminds.com