Many Finns know somebody whose behaviour becomes excessively strange and erratic when drunk. They are said to be unable to "hold their liquor".
Led by psychiatrist Roope Tikkanen, PhD, a new study has now demonstrated that a point mutation in the serotonin 2B receptor gene can render the carrier prone to impulsive behaviour, particularly when drunk.
The results also indicate that persons with this mutation are more impulsive by nature even when sober, and they are more likely to struggle with self-control or mood disorders.
The mutation identified in the study is present in 2.2% of the Finnish population, meaning that more than 100,000 Finns are carriers.
– The prevalence of the mutation was found to be 4 times higher in a Finnish criminal population, which implies a connection of the effects of the mutation on behavior, Tikkanen sates.
The serotonin 2B receptor mutation have so far only been found among Finns.– However, geographical boarders are no longer a limit as it was before, Tikkanen points out.
Little is known of the function of the serotonin 2B receptor in humans, but it is thought to be linked to impulsivity, which occurs with a number of mental health problems.
– Apparently, the impulsivity is also beneficial for survival since the mutation has been passed on, Tikkanen says.
If these results prove significant in larger clinical samples of individual patients who suffer greatly from difficulties in impulse control, several preventive measures could be taken.
– The most important measure would obviously be controlling the consumption of alcohol. Other measures would include attempting to achieve control over behaviour through cognitive-behavioural psychotherapy or medication.
The serotonin 2B receptor is a potential target for new medicines since there is no highly receptor-specific medicine available presently.
The discovery, published in the journal Translational Psychiatry,follows an original observation from 2010 on the mutation of serotonin 2B receptor among Finns.
The research took advantage of the unique data on impulsive sufferers of alcoholism and their relatives, compiled by Matti Virkkunen, Professor Emeritus of Forensic Psychiatry at the University of Helsinki.
The discovery is based on long-term research cooperation between the University of Helsinki Psychiatry Clinic and the Dr David Goldman’s laboratory of neurogenetics at the National Institute on Alcohol Abuse and Alcoholism in the United States.