FAMILY PROBLEMS LEAD BOYS TO TRY DRUGS, WITH GIRLS IT'S GENETIC, STUDY SAYS

Teenaged boys tend to experiment with drugs because of family dysfunction
or peer pressure, but drug use in girls is more sensitive to genetic
factors, according to a sweeping study of American teens.

The findings call into question whether the same tactics should be used to
prevent drug abuse in boys and girls, the authors say, and also provide new
insight into the chicken and egg problem of mental illness and drug use.

"In girls, there was a significant genetic influence on all substance abuse
in adolescence," said Judy Silberg, the lead author of the study on more
than 1000 teenagers in Virginia. "There was no significant effect of the
genes on drug use in boys."

That this difference -- between the natural drug user and the nurtured --
can be drawn along gender lines runs counter to the prevailing wisdom of
drug prevention policy, which tends to paint boys and girls as similar in
their drug experimentation -- girls are just a couple of years behind. By
the end of high school, most studies have shown the two sexes to be almost
neck and neck.

For this reason, education and prevention programs have tended to treat
boys and girls as being at equal -- and similar -- risk of drug problems.

Dr. Silberg said her study shows the sexes should be treated differently,
though. Girls' anti-social behaviours should be targeted directly, she
said, while treatment for boys ought to focus on "altering those family and
peer characteristics that are most influential."

The study looked at 629 pairs of twins over several years through childhood
into adolescence in Virginia; the twins allowed for a valuable comparison
between siblings who have identical genes but different life experiences
and social environments.

The findings also have implications for the study of mental illness in
teens, the authors say, because of the link they provide between early drug
use and depression.

The problem of drug use and depression is often addressed by clinicians
under the assumption that depressed people use drugs in an attempt at
self-medication, with mental illness as the underlying cause of the drug use.

The findings among the female teens, however, suggest early drug use
predicts depression much more reliably than vice versa.

In boys, environmental factors like family and friends seemed to be at the
root of both depression and drug use; there was no clear evidence that the
drugs were leading to depression or, conversely, that depression led them
to use drugs.