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Wednesday, December 8, 2010

Is ADHD Genetic?

The headlines are a-buzz with a "new study" that "finds first evidence that ADHD is genetic."

The media does an abysmal job reporting on scientific studies - so bad is their reporting that they should just stop it... now... please!

(here's a link to an article at Michigan State University's website about 1 million children misdiagnosed with ADD

First, a little bit about how news travels through our modern networks. Reuters, AP (Associated Press), and UPI will report to other corporations all the news that they see as "fit to print." Reuters and AP write up a blurb and send it out and other news corporations like CNN, Fox, MSN, all of their local networks can pick it up. Sometimes the big networks, newspapers, and magazines like CNN, NY Times, or Newsweek magazine will research the topic "in depth." On the internet, things just seem to be cut and pasted from one place to the next, occasionally with some added content or opinion. Websites will publish "news" that fits their ideology or position and ignore all else.

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The discrepancy between the conclusions of the scientists doing the study and the headline are the difference between night and day. Moreover, the conclusions of the scientists as stated in the news article are even more discrepant than reality.

Here's a quote from the Reuters report on this one study:

"Researchers who scanned the gene maps of more than 1,400 children found that those with ADHD were more likely than others to have small chunks of their DNA duplicated or missing."

That quote from Reuters is vague, from a scientific perspective. What does "more likely" mean? If even 80% of the children who had ADHD in the study also had DNA "chunk" problems, then that would be pretty  good evidence that there's a genetic problem. However, only a small number of the children in the study had "small chunks" of DNA duplicated or missing. The study included only 366 children who were diagnosed with ADHD and 1,047 children who didn't have ADHD. In this small sample, 15% of the ADD children had the chromosomal abnormality, while 7% of the non-ADHD group had the abnormality.

This one study does not and cannot 
lead one to conclude that ADHD is genetic!

What is very upsetting is that one of the scientist who lead the study, Anita Thapar, said, "the findings should help dispel the myths that ADHD is caused by bad parenting or high sugar diets."

Thapar's conclusions are baseless. You can't say that 15% of 366 children indicates that ADHD is "genetic" especially when 7% of the children who had the problem in the other group did not have ADHD. Only 15% of the ADHD children had the DNA issues = 55 of 366. If you take the 73 children from the non-ADHD and add them to the 55 in the ADHD group, you get 128 children, of which 42% had those with the gene problem present had ADHD.

It is false to conclude that the gene problems caused the ADHD.

 Here's an important issue, this study does not point to cause at all. All it says is that a small percentage of the children had gene problems. The fact that 75% of the small sample of ADHD children had normal genes, indicates that most ADHD is cause by something non-genetic!

It is possible that the genetic problems found in these children were caused by something else, for example, toxins in their environment. Do the parents have these gene problems? A few years ago, a study about Ritalin indicated that the drug can change the genetic expression of genes located in the brain's nerve cells. Genetics are complicated by the fact that environment plays a clear roll in how genes express themselves. There is evidence that exposure to certain pesticides during pregnancy is correlated with ADHD, as is smoking or drinking during pregnancy.

A very important question is, 
Why don't all children with this
gene "chunk" issue have ADHD?
Only 42% of the 128 children with
the gene chunk had ADHD.

What's very upsetting about Anita's comment in Reuters is that this study had nothing to do with parenting styles or high sugar diets. The distorted thinking that Anita is engaging in is common in the medical model. It's called "reductionist" thinking. That is, Anita is trying to reduce the cause of ADHD to one problem - genetics.

When will scientists come to terms with the fact that ADHD 
as well as all mental illnesses have multiple causal factors 
that interact with each other over the course of a person's lifetime. 
You just can't reduce cause to one factor like genetics.

What complicates the genetic research and which is mentioned in the end of the Reuters article, is that "a complex mix of genes and environment are likely to be the cause" of ADHD. That being said, why is the headline read, "Study finds first evidence that ADHD is genetic." We all know that Reuters is a news corporation and they sell news that people buy and people buy news that is sensational and exciting.

Consider this: ADHD drugs makes about $4 Billion dollars a year in sales for four corporations - about a billion each. Reuters didn't mention whether or not Anita and the other scientists or if Cardiff University have a financial relationship with any of the pharmaceutical corporations that make ADHD drugs.

I am concerned that Anita and Cardiff have financial ties to pharmaceutical corporations. I reviewed their study where they listed their funders, probably in order of dollar amount as: Action Research; Baily Thomas Charitable Trust; Wellcome Trust; UK Medical Research Council; and the European Union. Then I visited each of the funders' websites and I was unable to locate a list of their donors. For example, Action Research is a charity in the UK and France and they were vague about who donated to their cause. This is a concern because charities do not fund the research - donors fund the research. Who's doing the donating? For example, pharmaceutical corporations operate through charities like CHADD to indirectly promote their products; in fact, CHADD was partially founded by a pharmaceutical corporation.

It's an issue that I will continue to look into and report back about. It's the rule, not the exception for researches of ADHD, Bipolar Disorder, and other mental illnesses to have a financial tie to a pharmaceutical corporation. Studies have shown that scientists and doctors who have a financial ties to a pharmaceutical corporation are more likely to publish studies in favor of that corporation's drugs than scientists who have no financial ties.

Scientists who are funded by pharma 
may be prone to draw conclusions 
that favor medications.

Where this becomes an issue is how the scientists write up their conclusions from the raw data.  One thing is for certain, if you believe that your ADHD is "genetic" then you'll be more likely to try medications and doctors may be more willing to prescribe them. This is because we look at "genetics" as an absolute science, like physics. As though we cannot influence our genetic makeup through cognitive or behavioral techniques, or with ADHD, parenting techniques, and that we need medications to fix us.

Mental Health Advice Disclaimer
The information included in this post and blog are for educational purposes only. It is not intended nor implied to be a substitute for professional mental health treatment or medical advice. The reader should always consult his or her mental health provider to determine the appropriateness of the information for their own situation or if they have any questions regarding a mental health or medical condition or treatment plan. Reading the information on this website does not create a therapist-patient relationship.

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