DNA Determines the Ability to Quit Smoking

A recent study has suggested that the ability to quit smoking—easier for some, more difficult for others—may be tied to one’s genetic profile. According to an article published Tuesday in Translational Psychiatry, a recent “large-scale meta-analysis of Caucasian population” that combined information from 23 different studies involving over 9000 smokers (between 1994-2014) paid close attention to the variation in genes involved in the processing of dopamine—the neurotransmitter that helps regulate sensations of pleasure and reward. Addiction begins with the increased dopamine levels spawned by nicotine intake—probably not shocking information to those who know the hold of nicotine—but the study dug genetically into the test subjects to see if variants in genes make quitting necessarily easier or harder for individuals. As it turns out, the likelihood that some can give up smoking more easily than others seems related to evidence found in a gene called Taq1A. Within this DNA were subjects with different genetic variants—the study marked them as genotypes A1/A1, A1/A2 and A2/ A2. According to the overall, long-term analysis, “individuals with the homozygous Taq1A A2/A2 genotype are more likely to be successful in abstinence from cigarette smoking than those with A1/A1 or A1/A2 genotypes. The study observed that smokers who carry the A2/A2 gene had a largely easier time giving up the habit over others. (Without going too deep into heavy scientific chatter, the study’s research indicates the A2/A2 gene allows for a better controlled reception of dopamine, thus reducing the addictive effects of nicotine.)

The study determined there was a “significant association” between having the A2/A2 genetic variant and an increased ability to successfully stop smoking. The authors of the Translational Psychiatry article suggest this data could eventually help with the development of smoking cessation treatments, based in part on genetic predispositions.