The findings were British scientists drawn to examine the brains of rats and humans. At first scientists observe the mice removed genes RASGRF2, which showed that they have alcohol addiction-seeking behavior and the release of dopamine neurons decreased significantly.

Then the scientists conducted brain scans 663 teenagers at 14years old and found that those who have genetic variants of RASGRF2, the activity of brain areas generate dopamine. To test, the research team analyzed drinking behavior of adolescents. Those adolescents who have genes of RASGRF2 started drinking more regularly and those who do not have genes RASGRF2 start drinking in two years later.

The findings helped explaining phenomenon some young people prefer to be drunk all day. "If people have a variant of genes RASGRF-2, drinking alcohol gives them a stronger sense of joy, leading to risk of heavy alcohol addiction", Gunter Schumann, head of research at Mental Health Institute Imperial College London said.

It is known that alcohol addiction, drugs and other addictive substances activate dopamine system of the brain, causing excitement to the user. According to the World Health Organization, the world has about 2.5 million people die each year due alcohol, accounting 3.8% total deaths worldwide.