Genes may affect nicotine patch success

Women smokers with a particular genetic variation are more likely to benefit from nicotine patches when trying to quit than others, a new UK study suggests. Researchers at the University of Oxford studied 445 women and 307 men who had been heavy smokers, who were given either nicotine or control patches for twelve weeks. They found that women with the 'T' version of the dopamine D2 receptor gene (DRD2) were more likely to stop smoking if they wore a nicotine patch, whereas women with the 'C' version did not benefit from wearing a patch. For the men in the study, their DRD2 gene type made no difference to their ability to stop smoking when wearing a patch.

After 12 weeks of wearing the nicotine patches, 23 per cent of women with either one or two T versions of the gene had stopped smoking, compared with only 13 per cent of women with two C versions. Since 12 per cent of 'CC' women wearing dummy patches also managed to quit, the researchers conclude that the nicotine patches may not benefit such female smokers. For men wearing nicotine patches, 25 per cent of those with one or two T versions had stopped, compared to 23 per cent of those with two C versions.

The findings, published online in the British Medical Journal, suggest that social factors may play a bigger role than nicotine dependence in women's smoking behaviour, compared to men. Around 60 per cent of the men and women in the study had inherited two C versions of the DRD2 gene, which has previously been linked to smoking behaviour. Lead author Patricia Yudkin said that further studies needed to be done, but in the future, women could be tested quickly and easily for DRD2 genotype. 'We could also advise those with the CC genotype not to use nicotine replacement', she said, adding that 'other forms of therapy are likely to work better for them'.