Gambling addicts may have a genetic predisposition to become hooked, the first scientific study of its kind has found.

Addiction may also change people’s brains to become more sensitive to the thrill of betting, the researchers found.

For the first time, they took a group of people with gambling disorder - now recognised as a condition treatable on the NHS - and compared them with their siblings who were not addicts and a control group.

They discovered that the siblings were bigger risk takers and more impulsive than a control group, evidence of a genetic predisposition to gambling.

The problem gamblers and their siblings were more likely to act impulsively in the face of negative emotions, and placed larger bets when they faced higher-risk odds.

There was, however, no difference in the brain scans of non-gambling siblings and the control group, suggesting that the brain activity found in the addicts may have developed as a result of their gambling.

Previous research using MRI brain scans show Fortnite and other addictive video games can have a similar effect on children’s brains as drug abuse or alcoholism.

They show the “reward” system in the brains of young heavy users of social media and video games display the same changes in function and structure as those of alcoholics or drug addicts.