August 13, 2011 – Medical News Today reported that a new study, led by The Hospital For Sick Children and the University of Toronto have made a very interesting discovery in the neurological field. The study has uncovered more genes in ADHD and an overlap in some of those genes. The study, published in the online edition of Science Translational Medicine, also links susceptibility of Autism and other neurological disorders.
Genes Identified in Neurological Disorders: ADHD and Autism
Led by Dr. Russell Schachar and Dr. Stephen Scherer, the study examined the DNA patients who have ADHD. The study looked for copy number variants (CNVs) which are insertions or deletions that affect the genes. In three cases, CNVs were found in the child’s genes but not in their parent’s genes, showing the mutation to be specific to the child only. ADHD is believed to be a hereditary condition.
In previous studies, certain genes had been identified in other neuropsychiatric conditions including autism spectrum disorder or ASD. Of 349 children, nine tested positive for ASD and also carried CNVs related to ADHD and related disorders.
Gene Identification Helps to Diagnose ADHD, Autsim
While concrete testing for neurological disorders such as ADHD are still not 100% proven, the gene identification gets scientists one step closer to being able to understand ADHD and other mental disorders.
Dr. Schachar reports that people react in different ways and each case is quite unique. Many people who have ADHD also display other conditions such as, but not limited to, anxiety, mood, language or conduct disorders. It’s also noted that 75 percent of individuals who have ASD also have deficits in their attention and/or display hyperactivity.
What is ADHD and ASD
ADHD is the abbreviation for attention deficit hyperactivity disorder and affects four percent of school-age children worldwide. Symptoms of ADHD are hyperactivity, impulsiveness and lack of attention. It often leads to learning difficulties, problems with social skills and mood disorders.
ASD, also known as autism spectrum disorder, affects approximately one in 100 children across North America and causes problems with communication, behavior and social concepts.
As with many disorders of the brain, there are currently no concrete tests to diagnosis conditions like ADHD and physicians rely on perception of behavior in various settings. Many factors must be ruled out first such as eye or ear problems and all results may not be completely un-biased.
Todd Elder, of Michigan State University, published a study in 2010, linking rates of ADHD diagnosis with children who were the youngest in their classroom. He noted that up to 60 percent of children who were the youngest in their grade level, were more likely to be diagnosed as ADHD, simply because they were younger then their peers. This equates to the possibility of nearly 1 million US children being misdiagnosed with ADHD and between $320 million to $500 million being spent on unnecessary use of medications to treat the disorder.
Since current diagnosis of the disorder relies on teachers and caregivers evaluating the patient based on observation, it is very likely that a five year old will be perceived to be more hyperactive and immature than their six year old peers. Elder’s study has led many parents and educators to only allowing a child to enter kindergarten if he or she has reached the age of five on the actual start date of school and if they have not yet turned five, they are recommended now to wait another year before entering the school system.
This new study will increase the chances of properly diagnosing conditions such as ADHD and stop unnecessarily medicating children who do not need powerful stimulant medications.