Genes linked to smoking in pregnancy identified

The study also showed men experience more long-lasting effects when their mother smokes while pregnant than women - including dying younger if they go on to smoke themselves.

A team of researchers from the University of Aberdeen studied more than half a million people across the UK to understand the effects of smoking in pregnancy and how they can persist throughout adulthood.

The group, led by Professor Paul Fowler, chairman in translational medical sciences, used the genetic relationship between mothers and their adult children to conduct the first large-scale genetic analysis of maternal smoking.

They identified several gene variants that increase the likelihood of maternal smoking, opening up potential to develop more targeted treatments to stop people smoking.

Using data from 500,000 people across 22 centres in Scotland, England and Wales, the team were able to investigate the genetic, biochemical and socio-demographic factors associated with smoking during pregnancy.

They found at every stage, male fetuses and adult sons were more affected by maternal smoking during pregnancy than females.

This manifested as changes in levels of various genes in male fetal livers as early as at 17 weeks pregnant right through to adult males having shorter life expectancy.

The team found if the adult man stops smoking, or did not smoke at all, they can counter these risks.

The increased likelihood for an early death was reduced in men who reported to have never smoked cigarettes themselves.

The new insight could help devise more effective strategies to mitigate the adverse effects of maternal smoking exposure.

The study also found men are more likely to develop cancer in adulthood and are more susceptible to developing type two diabetes than females.

Women are more likely to develop digestive and reproductive disorders as well as mental health issues.

Postgraduate researcher Mihail Mihov, who conducted the research as part of their PhD studies, said: "Maternal smoking during pregnancy has been linked to many health issues for babies.

"However, we previously had limited knowledge about which processes in the womb are influenced by maternal smoking and how they translate to diminished health later in life.

"Our findings show that maternal smoking impacts baby's health, particularly for males, from as early as the second trimester and this continues throughout adulthood.

"However, we did find that this can be somewhat reversed. Our results indicate that smoking cessation or, ideally, not smoking at all in men can counter the increased risk of early death in adulthood."

Mihov said for the first time several gene variants were identified, which increased the likelihood that a mother will smoke or be addicted to smoking, even during pregnancy.

"This opens avenues where we can look for potentially gene-specific targetable pathways to smoking cessation and therefore offer ways to decrease the societal burden of maternal smoking in our ageing society."

Australian Associated Press