New research suggests boys who smoke in their early teens risk damaging the genes of their future children.
Researchers from the University of Southampton and University of Bergen examined the long-term consequences of teenage smoking.
The collaboration was supported by the NIHR Southampton Biomedical Research Centre (BRC).
They found boys who smoke at an early age may alter the DNA of their future children. These changes put them at greater risk of developing asthma, obesity and low lung function.
Researchers say the study highlights the need for more action to tackle teenage vaping.
Their findings are published in Clinical Epigenetics.
Studying changes to DNA
The researchers analysed data from 875 people aged 7-50.
They looked at the participants’ epigenetics - how a person’s environment affects the way their genes work, for example by switching them ‘on’ or ‘off’. They also looked at the smoking behaviours of their fathers.
The team found epigenetic changes at 19 sites mapped to 14 genes in the children of fathers who smoked before the age of 15. These changes are associated with asthma, obesity and wheezing.
Prof Cecilie Svanes is a Professor at the Centre for International Health, University of Bergen. She said:
“Previous research has shown that the health of future generations depends on the actions and decisions made by young people today. This is true long before they are parents – particularly for boys in early puberty.”
She added: “It is really exciting that we have now been able to identify a mechanism that explains our observations in the cohorts.”
“A critical window”
The study suggests starting to smoke as a teenager is particularly dangerous. Dr Negusse Kitaba, Research Fellow at the University of Southampton and co-lead author, said:
“Changes in epigenetic markers were most pronounced in children whose fathers started smoking during puberty.
“Early puberty may represent a critical window of physiological changes in boys. This is when stem cells are being established which will make sperm for the rest of their lives.”
The team also compared the paternal preconception smoking profiles with people who smoked themselves and those whose mothers smoked before conception.
The University of Bergen’s Dr Gerd Toril Mørkve Knudsen, who was the co-lead author of this study, explained:
“Interestingly, we found that 16 of the 19 markers associated with fathers’ teenage smoking had not previously been linked to maternal or personal smoking.
“This suggests that these new biomarkers may be unique to children whose fathers have been exposed to smoking in early puberty.”
Teenage vaping
The number of young people smoking has fallen in the UK in recent years. However, the researchers are concerned about children taking up vaping.
Prof John Holloway is a Professor of Allergy and Respiratory Genetics at the University of Southampton. He is also part of the Respiratory and Allergy theme at the NIHR Southampton BRC. He explained:
“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 boys, are being exposed to very high levels of nicotine through vaping.
He added: “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 be sure vaping will have similar effects across generations, but we shouldn’t wait to find out. We need to act now.”
Working with young people
The new findings have significant implications for public health.
They suggest a failure to address harmful exposures in teenagers today could damage the respiratory health of future generations. This could also increase health inequalities for decades to come.
Southampton’s LifeLab programme engages with young people to show how lifestyle choices at an early age can drastically their health and the health of their future children. They hope to empower young people to make healthier choices.
The programme is a partnership between the University of Southampton, the NIHR Southampton BRC and University Hospital Southampton.
Dr Kath Woods-Townsend, LifeLab Programme Manager said:
“Parents, teachers and young people themselves have concerns about the impact of vaping.
“We’re working with a youth panel to understand the role vaping plays in their lives and to co-create resources that will help inform young people about the risks.”