A teenager's odds of developing moderate to severe acne may depend largely on whether his parents had the problem, a new study suggests.

Most teenagers have occasional acne breakouts due mainly to hormonal changes, particularly elevations in testosterone. However, some teens and adults develop more extensive acne that require treatment with topical prescriptions or oral medication like antibiotics or isotretinoin, a synthetic form of vitamin A.

It is unclear why some teenagers are prone to more severe acne.

According to a Reuters report, the new findings, from a study of 1,000 Iranian high school students, suggest that family history may be key.

Researchers found that 14 per cent of the students had moderate to severe acne, with the prevalence varying significantly based on family history. Of those teens whose parents or siblings once had moderate to severe acne, 20 per cent had the same problem.

In contrast, the rate was 10 per cent among teens with no such family history, the researchers reported in the Journal Of Investigative Dermatology.

The findings point to the importance of genetics in whether a teen will have more severe acne, according to senior researcher Christos Zouboulis, of the Dessau Medical Center in Germany.

'Therefore, children with parents who experienced severe acne have to be followed up on a regular basis and be treated earlier when acne lesions occur," he told Reuters Health.

Dr Zouboulis said that a mother's history may be particularly important.

Teens, whose mothers had moderate to severe acne, were three times as likely to develop the problem as their peers were. When fathers had the skin condition, their children's risk increased two-fold.

This, according to the researchers, raises the possibility that a genetic characteristic related to the X chromosome plays a role. (Everyone inherits an X chromosome from his or her mother, while fathers contribute an X chromosome to female children only.)

This article was first published in Mind Your Body, The Straits Times.