[user_7832]

Unfortunately I'm not a doctor or researcher to be able to give a definitive answer, but I don't think these things can cause ADHD - though they can likely worsen symptoms, for both people who have it and those who don't. But I suspect such an effect would be reversible, unlike (genetic components of) ADHD.

[988747]

I thought that the researcher that 'discovered' ADHD admitted oh his death bed that it was just a scam he invented to make money on the drugs to cure it.

[user_7832]

Oh, trust me I wish I never could relate to the ADHD symptoms, but for better or for worse it exists. Heck, the concept of Alzheimer's sounds very suspicious ("How do you forget your name!?")... until you see someone with it and then it's just sad :(

[ellopoppit]

There is no known gene which causes ADHD.

Like all other conditions in the DSM, there is no objective biological diagnostic criteria

[kortex]

There's no one gene, but aside from very specific things, there's hardly one gene for any condition, but ADHD is highly heritable, and we already know several strong candidates. DRD4-R7, COMT Val158Met, TPH2, a couple others have been identified recently. Also, PET scans and in some cases high-density EEG can pick it up, the thing is, those are quite expensive and don't really even tell you that much, whereas psychological evaluation tells you much more qualitatively.

[ellopoppit]

There is neither one or many genes or any objective biological test that is used to diagnose any psychiatric condition in the DSM.

"psychiatric diagnosis still relies exclusively on fallible subjective judgments rather than objective biological tests"

-Allen Francis, Professor and Chairman Emeritus of the Department of Psychiatry and Behavioral Sciences at Duke University School of Medicine, chair of the American Psychiatric Association task force overseeing the development and revision of the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV)

[stevenhuang]

The mechanism of gene expression means the presence of certain genes may cause an individual to be more or less susceptible to certain stimuli.

So yes, the presence or absence of genes alone may not determine much, but together taking account to one's environment and upbringing, may have explanatory power.

It's similar to medical diagnoses where the presence of X genes mean someone is Y% more likely to exhibit Z condition.

[user_7832]

Perhaps specifically saying gene isn't accurate, but adhd is highly heritable (anywhere between 40 to 80% depending on which paper you look at)

[ellopoppit]

Indeed, social behaviors are highly heritable, we don't need a scientific paper to tell us that.