August 13, 2008

Why worrying runs in the family Why worrying runs in the family

Publication Evening Herald

Date 11th August

By Steve Connor

Some people are more prone to extreme anxiety because of a genetic mutation they have inherited, according to a new study. The mutation is found in about half the population but it exerts its effect on the one in four people who have inherited both copies of it from their parents, it found. Such people are at significantly higher risk of being more anxious than the general population and of suffering from anxiety-related conditions such as post-traumatic stress disorder and obsessive-compulsive illnesses.

Scientists say the findings show that it is possible to identify genetic differences between people that directly affect the chemicals in the brain that influence variations in psychological traits. Researchers believe the discovery opens the way to identifying further genes that can le'ad to someone becoming nervous to the point of developing a psychological illness. "To identify this first candidate for genes associated with an anxiety-prone personality is a step in the right direction," said Christian Montag of the University of Bonn, a member of the research team. "It might be possible to prescribe the right dose of the right drug, relative to genetic make-up, to treat anxiety disorders," Dr Montag said.

The study focused on a gene known as COMT, which controls an enzyme that breaks down and so weakens the signal of dopamine, a key neurotransmitter in the brain associated with several psychological conditions, such as Parkinson's disease and schizophrenia. The gene comes in two variations, met158 and val158, and the people who are most likely to be anxious are those who have inherited both copies of the met158 gene variant from each of their parents.

In the European population, about 25pc of people have this genetic make-up. The theory is that people with both copies of the met158 gene variant have a stronger dopamine signal in their brain, which results in an "inflexible attentional focus" they cannot tear themselves away from an unpleasant stimulus even if it is a bad one.