Study Focuses on Genetic Links to ADHD
Medical research is shedding more light on the root causes of attention deficit hyperactivity disorder, (ADHD), one of the most common psychiatric disorders seen in children. It is thought that between 3-5% of children in the US have ADHD. It is a disorder which has far reaching effects on academic performace, social relationships and familial harmony. Researchers have slowly been gathering evidence over the past decade which shows that the neurological structure of the brains of those with ADHD are different from those without the condition. The etiology of ADHD is unknown, but it has been long suspected that there is a genetic component to the disorder, as it very commonly runs in families.
A study recently published December 4th in the journal Nature Genetics suggests that there may also be genetic variations in the brains of persons with ADHD. Researchers at the Children's Hospital of Philadelphia examined the entire genome of 1000 children diagnosed with ADHD and compared them to 4100 children without the disorder. The research team was looking for copy number variations (CNVs) which are deleted or duplicated sequences of DNA.
The scientists identified four genes which had significant numbers of CNVs in children with ADHD. These four genes are members of the glutamate receptor gene family. Glutamate is a neurotransmitter, a protein which transmits chemical signals throughout the brain. It is thought that up to 10% of children with ADHD have alterations in these four aforementioned genes. Dr. Josephine Elia, a member of the research team and a psychiatrist with a special interest in ADHD stated that "identifying a gene family responsible for 10 percent of cases is a robust finding in a common neuropsychiatric disorder such as ADHD". The research results suggest a jumping off point for further investigation, and hopefully targeted treatment for this subset of individuals with ADHD.
Image courtesy of Carl C.