October 17, 2018

expert reaction to nicotine use in male mice and offspring’s cognitive ability

Research published in PLOS Biology demonstrates that the offspring of nicotine-exposed male mice demonstrate behaviors associated with ADHD and autism in human.

Dr Susanna Roberts, Postdoctoral research associate, Institute of Psychiatry Psychology & Neuroscience, King’s College London, said:

“This thorough study by McCarthy et al (conducted in mice) addresses an important issue: the potential biological impact of smoking in fathers on their offpsring. As noted by the authors, the majority of research to date has focussed on the potential of maternal influences on offspring outcomes. The results support a transgenerational effect, whereby nicotine exposure in male mice was associated with behavioural difficulties in the offspring and subsequent generation. Studies demonstrating transgenerational (or inherited) epigenetic marks, particularly those related to environmental exposures, have been a source of some scepticism in recent years, but this study utilises multiple types of biological and behavioural data to corroborate their findings and imply potential mechanisms (albeit focussing on a small set of genes).

“However, despite the interesting results, it is difficult to extrapolate the importance of these effects in humans, where the causal pathways to behaviour and influences on biology are immeasurably more complex. Solid replication and further research in humans is needed before the implications are fully understood. Nevertheless, this research raises the importance of considering both maternal and paternal influences for complex traits.”

Prof Peter Hajek, Director of the Tobacco Dependence Research Unit, Queen Mary University of London (QMUL), said:

“The press release appears hugely cavalier in blurring the distinction between mice and men (and not even stating that it is talking about mice rather than people in the middle paragraph). Twelve 8-10 week old mice were forced to absorb what for them are huge doses of nicotine for the next 12 weeks and this seems to have severely damaged their sperm and their offspring. Such studies rarely translate to human smokers.”

* ‘Nicotine exposure of male mice produces behavioral impairment in multiple generations of descendants’ by McCarthy et al. will be published in PLOS Biology at 19:00 UK time on Tuesday 16^th October, which is also when the embargo will lift. 

Declared interests

Dr Susanna Roberts: “No conflicts of interest”

Prof Peter Hajek: “No conflicts of interest”