Boys who smoke in their early teens risk damaging their future children, increasing the chances of developing respiratory diseases, obesity, and lung problems, according to a study published in Clinical Epigenetics. This is the first study to describe the mechanism behind the impact of fathers’ early teenage smoking on their future children.
A team from the University of Southampton, UK, and the University of Bergen, Norway, investigated the epigenetic profiles of 875 people and the smoking behaviours of their fathers.
Researchers identified changes in 19 different sites mapped to 14 genes in the children of fathers who smoked before the age of 15. Many of these genes are associated with breathing function and cause asthma, obesity, and wheezing. “Our studies in the large international RHINESSA, RHINE, and ECRHS studies have shown that the health of future generations depends on the actions and decisions made by young people today – long before they are parents – in particular for boys in early puberty and mothers/grandmothers both pre-pregnancy and during pregnancy,” said Professor Cecilie Svanes from the University of Bergen and Research Director of the RHINESSA study. “It is really exciting that we have now been able to identify a mechanism that explains our observations in the cohorts.”
“Changes in epigenetic markers were much more pronounced in children whose fathers started smoking during puberty than those whose fathers had started smoking at any time before conception,” added co-lead author of the paper, Dr. Negusse Kitaba, from the University of Southampton. “Early puberty may represent a critical window of physiological changes in boys. This is when the stem cells are being established, which will make sperm for the rest of their lives.”
The study also assessed whether mothers were smokers or not at an early age. “Interestingly, we found that 16 of the 19 markers associated with fathers’ teenage smoking had not previously been linked to maternal or personal smoking,” says Dr Gerd Toril Mørkve Knudsen from the University of Bergen and co-lead author of the study. “This suggests these new methylation biomarkers may be unique to children whose fathers have been exposed to smoking in early puberty.”
The number of young people who smoke has decreased in the past few years, but the authors are concerned about children taking up vaping. “Some animal studies suggest that nicotine may be the substance in cigarette smoke that is driving epigenetic changes in offspring. So it’s deeply worrying that teenagers today, especially teenage boys, are now being exposed to very high levels of nicotine through vaping,” said Professor Holloway. “The evidence from this study comes from people whose fathers smoked as teenagers in the 60s and 70s when smoking tobacco was much more common. We can’t definitely be sure vaping will have similar effects across generations, but we shouldn’t wait a couple of generations to prove what impact teenage vaping might have. We need to act now.”
To address these issues with young people, the University of Southampton has developed a program called LifeLab to engage with young people and show how lifestyle choices can impact their health and the health of their future children. “Parents, teachers, and young people themselves are concerned about the impact of vaping. We’re working with our Youth Panel to understand the role vaping plays in their lives and to create resources that will help inform young people about the risks,” concluded Dr Kath Woods-Townsend, LifeLab Programme manager.
Kitaba NT, Knudsen GTM, Johannessen A, Rezwan FI, et al. (2023) Fathers’ preconception smoking and offspring DNA methylation. Clin Epigenetics. 15(1):131. doi: 10.1186/s13148-023-01540-7