This week I read a really interesting article about ADHD called "First Direct Evidence That ADHD Is a Genetic Disorder: Children With ADHD More Likely to Have Missing or Duplicated Segments of DNA" . The article was about the researchers identifying a gene that could be linked to ADHD. This is different than what is previously thought; that ADHD was caused by poor parenting skills or poor diet. The researchers tested 1,000 unaffected children and 336 children affected by ADHD and compared their genomes. They found that children who had been diagnosed with ADHD have significantly higher rates of duplicated or missing sequences of DNA. Also, it has been identified that the parts of the DNA that have been affected are also the parts that influence susceptibility to Autism and Schizophrenia. It is thought that ADHD is not caused by just one genetic change but by many genetic changes and how they interact with the person's environment. The researchers do not think that genetic testing would be a good way to diagnose children. They think the clinical assessment already in place to test for ADHD is good enough. However, this research is important because it provides new information about the disease and also helps to remove the stigma of ADHD being cause by poor diet and poor parenting skills.
And finally, the *only* man in Minnesota who says there is no God has suddenly become an arbiter on mental health...
unfacts.org/factsforum/viewtopic.php?t=4080
COME SEE A PHOTO OF MABUS AND AN EXPLANATION OF IT!
Interesting topic. I'm not sure the nuances about the genetics are clear in your post:
The researchers do not think that genetic testing would be a good way to diagnose children. They think the clinical assessment already in place to test for ADHD is good enough..
Why would genetic testing not be a good idea?
From the paper:
"ADHD is not caused by a single genetic change, but is likely caused by a number of genetic changes, including CNVs, interacting with a child's environment," explains Dr Kate Langley. "Screening children for the CNVs that we have identified will not help diagnose their condition. We already have very rigorous clinical assessments to do just that."
So, if I understand correctly, although there is now direct evidence for a genetic link, we don't have a direct genetic cause for ADHD, and a genetic test would be insufficient to diagnose ADHD.
Lisa,
Did you read the original article? You should. ScienceDaily presents a lot of interesting new research but it doesn't always present that research particularly well. I think the articles are mostly written by PR departments and not science journalists. At any rate, its misleading to say that this paper is the first direct evidence for a genetic link to ADHD. ADHD is probably one of the most well-studied mental disorders in children and there are have been lots of candidate gene studies. For example, previous studies have shown certain alleles of the serotonin transporter gene are more prevalent in children with ADHD than children without. Is that not a direct genetic link? Also ADHD has not previously been though to be due purely to aspects of the child's environment, like bad parenting or diet. Quantitative genetic studies have long provided supporting evidence for a genetic contribution to developing ADHD.
I think what this paper shows is that ADHD symptoms can arise from a variety of genetic problems (like both insertion and deletions in the genome).
Cheers,
kzk