I could scarcely believe my eyes last week when BBC news made its principal story one morning last week a genetics paper purporting to “prove” the ADHD was a genetic disorder (HERE ). In fact, the study had really only at best discovered a modest statistical association between a genetic pattern (against controls) in 15% of cases. The authors no doubt eager to draw attention and further patronage for their activities could probably scarcely believe their luck with such a publicity coup. Equally fascinating was the speed with which the BBC realised its boob. By 9.30 am veteran correspondent Fergus Walsh was reporting (HERE ):
“There is a danger of reading too much into new research in the Lancet on attention-deficit hyperactivity disorder (ADHD). The headline of the Lancet press release says: "Study is the first to find direct evidence that ADHD is a genetic disorder". One of the authors, Professor Anita Thapar is quoted as saying: "Now we can say with confidence that ADHD is a genetic disease and that the brains of children with this condition develop differently to those of other children".
“That's that then. Or perhaps not. Because those bold claims do not seem to be borne out by the actual research paper. The study analysed DNA from 366 children with ADHD and 1,047 controls. They found that those with ADHD were twice as likely to have chunks of DNA missing or duplicated, areas known as copy number variants. This genetic variation was also found to be more common in brain disorders.
“I have done the sums and around 15% of the ADHD children had the genetic variant and about 7% of the control group did not. Put that another way, it affected one in seven of the ADHD group and one in 14 of those without.
“That also means that seven out of eight of the ADHD group did not have the genetic variant - which hardly justifies Professor Thapar's confident assertion that ADHD is a genetic disease. I put this to Professor Thapar and she was keen to stress that she was not asserting that genes alone were responsible for ADHD but rather a complex mix of genes and environmental factors.”
We might even go further and point out that if not children with these gene variations have ADHD then you can scarcely have done more than establish a possible vulnerability to external factors. Let’s face it, even Fergus Walsh could work that one out. He might even have added how disappointing all this was after decades of gene research. Well, that would have been going rather far for the BBC!
The truth is that the amount of noise coming out of the gene research fraternity these day is in inverse proportion to its achievement. Last year a leading biologist Steve Jones wrote in the Daily Telegraph (HERE ):
“It's not done to kill the goose that lays the golden eggs, nor to bite the hand that feeds you – nor, in my own profession, to criticise the research programme of the Wellcome Trust, an enormously rich charity that paid much of the bill to read the message written in human DNA. Not done, perhaps, but a pack of renegade biologists has turned on that source of nutrition to claim that what it is doing is welcome, but plain wrong.”
Jones points out that in most cases there are no specific genes connected with medical conditions and that this is no longer a sensible way to research illness:
“In other words, our chances of being born with a predisposition to a common illness such as diabetes or heart disease are not represented by the roll of a single die, but a gamble involving huge numbers of cards. Some people are dealt a poor mix and suffer as a result. Rather than drawing one fatal error, they lose life's poker game in complicated and unpredictable ways. So many small cards can be shuffled that everyone fails in their own private fashion. Most individual genes say very little about the real risk of illness. As a result, the thousands of people who are paying for tests for susceptibility to particular diseases are wasting their money.”
Of course, if you were allowed to say this in a wider public arena about autism/gene studies as well ADHD/gene studies we might have been spared the prolonged farce of the Pinto study earlier this year (HERE and HERE )with 176 authors (including Geraldine Dawson of Autism Speaks), complete with abusive comments from David Gorski of Science blogs (HERE ), and we might have been spared the new collection of ‘dinosaur’ studies from Autism Speaks so aptly reported on by Teresa Conrick the other day (HERE ).
But, of course, with autism – for public purposes – the less you find, the greater the success, and gene studies are the perfect medium.