Revolution robbed alcogenes of brakes

Photo: Margus Ansu

Girls born during Estonia’s Singing Revolution took their initial sip of alcohol a lot sooner than young ladies just some few years older. This cannot be explained by political shift alone – genes have played a role.

Here’s the most striking fact found in a recent scientific article by group of scientists under leadership of Jaanus Harro, professor of psychophysics in University of Tartu: in an age-group studied, girls with a definite gene variant got their very first drinking experience three years sooner than older girls with that very gene variant. The article is about to be published in the magazine Psychopharmacology.

In the study, comparing behaviour and genes of young people born in 1982/1983 and 1988/1989, various expected differences in alcohol consumption were revealed: that the boys start drinking a bit sooner than girls; and that the age of the fist drink is getting «younger», as in many European countries.

Even so, it was also found out that the so-called risk-type younger girls were the very first, among peers, to taste alcohol – even before boys – while girls of the same genotype and only six years older were the last to try alcohol among peers.

«To my knowledge, this is the first time where, in psychiatry and behavioural science, relationship between brain-activity-affecting gene variant and birth cohort has been shown,» says Mr Harro.

The study surveyed the serotonin-transporter gene which, according to Mr Harro, is the most studied gene in behavioural science. One so-called shorter variant of a certain area of that gene has been linked to greater risk of various anxiety disorders and, overall, with greater sensitivity and size of the part of the brain known as amygdala. The study specified as risk-group the young people, about one fifth of all surveyed, possessing short variant for both gene copies.

«Such young people are more inclined towards extremes and are more sensitive towards social stimuli,» says Mr Harro. This may amount to one explanation if the gap discovered. «This is environment pressure effect, to which these youth yield better,» said he.

«During the years of the critical formation of the older group, alcohol was harder to obtain and more condemned; later, consumption of alcohol rather became the social norm,» explains the professor.

At the same time, the effects of the gene variant are not negative only, underlines Mr Harro. According to him, the gene variant enhances general receptivity, both towards the bad and the useful. Thus, earlier research reveal these very youth being faster at acquiring higher education, as well as possessing other socio-economical advantages.

«The maximal freedom ruling in the Estonia of the 1990ies serves to show the high effects of genotype variants affecting brain activity,» says Mr Harro, finding Estonia as a unique study environment in the world due to fast changes during the transformation. 

«The gene’s impact on regular consumption is revealed later, as amounts of alcohol increase,» supposes Mr Harro.

The professor vowed the group would continue studying the same youth, to discover other links between genes and environment. Among other things, they will be monitoring how various ages of initial alcohol consumption affect human health.