Byline: Charlotte Haigh
Watching a child tear around a room, unable to sit still for more than a few seconds, an outsider might be inclined to blame their upbringing.
Parents of these seemingly uncontrollable children have grown used to rolled eyes, tuts and nasty comments from disapproving passers-by. And when such children were diagnosed with attention deficit hyperactivity disorder, some saw it as an excuse for bad behaviour and bad parenting. But new research has linked ADHD firmly to genetics.
The study, led by Professor Anita Thapar at Cardiff University, found children with ADHD are twice as likely to have bits of genes either missing or duplicated. And those
with ADHD and learning difficulties are six times more likely to have these gene variations. That gene area has also been linked with schizophrenia and autism.
So for the first time a significant link between genetic abnormalities and ADHD has been proved. At last parents can show there is a reason their child is misbehaving and experts can start looking for effective treatments.
What is ADHD?
"It's a developmental condition characterised by inattention and difficulty concentrating, along with hyperactivity and impulsivity. Although some may have the disorder without the hyperactive element," says Dr Dinah Jayson, consultant child and adolescent psychiatrist at Trafford Healthcare NHS Trust, Manchester.
Those with it are at much higher risk of getting into trouble at school and falling into crime, substance abuse, and broken relationships, if untreated.
It's thought to affect up to 5% of the population, although many people go undiagnosed.
"It's possible we're more aware of it because society has changed so much. In the past, we tended to do manual jobs, so someone with ADHD may not have stood out in that context," says Dr Jayson.
"Now, we prize being able to sit quietly and concentrate on paperwork - things someone with ADHD may find impossible."
Although ADHD is normally associated with children, it often stretches into adulthood, too.
"While some outgrow it, 60% will have symptoms as adults, with half of these still needing medication," says Dr Jayson.
An adult with ADHD will typically find it difficult to complete a task or concentrate on a conversation. To others they may come across as rude and disorganised." adds Dr Jayson.
Here comes the science part..
"The new study was the first to look directly at the genes," Dr Jayson says. However, genes don't tell the whole story. The genetic variations raise the risk of ADHD, but don't guarantee the disorder will develop.
"Environmental factors play an important role," says Dr Jayson. "If the mother is very anxious during her pregnancy, high levels of stress hormones in the womb can double the chances of ADHD if the child already has a genetic risk.
"And, in childhood, if there's disruption of some kind in the family home or lack of structured activities, support or supervision, that may contribute to problems in a child with a genetic tendency to ADHD."
It isn't about bad parenting - sometimes the environment that provides the chance for ADHD to develop is due to circumstances - where you live, a lack of support or an illness.
There was a popular myth that children with ADHD had problems because they were fed on foods high in additives and sugar.
Not so, says Dr Jayson. "Some additives can produce ADHD-like symptoms in children, but in those with the disorder the symptoms will persist even if the additives are removed from their diet."
Get a diagnosis
If children with ADHD are untreated, they are more likely to fall behind at school and be branded troublemakers. This, Dr Jayson says, can trigger a downward spiral with other behavioural issues or depression and anxiety, piling on top of the ADHD symptoms. …