Most smokers are having a difficult time to quit their smoking habit because their dependence may be well explained in part by genetics, a new study said.

Scientists have recently identified genetic variants associated with smoking behaviors that have a considerable impact on ones health.

Patrick Sullivan and Helena Furberg, from the Chapel Hill School of Medicine and University of North Carolina, led the Tobacco and Genetics Consortium (TAG), the largest genetic  study of smoking. This consortium collaborated with scientists from 16 large genetic studies worldwide.

They have compared the DNA profiles between non-smokers and smokers in order to examine whether genetic variants affect people when they start to smoke.

They also studied whether genetic variants affects the number of cigarettes smoked per day, age when people begin to smoke and whether smoker s are able to quit it.

The team has found out that three genetic regions were linked with the number of cigarettes smoked per day, one region with smoking initiation and one variant associated with smoking cessation.

We hope that this study will allow researchers from multiple disciplines to widen their understanding of the genetics of addiction and evaluate how drug-gene interactions could be of use to create therapies to improve the rates of smoking cessation, said Furberg.

Huge amount of work needs to be done before our findings can be used to treat smokers who want to quit. At this time, testing for these variants will not result to anything meaningful about nicotine and smoking dependence risk. Of course, all smokers are encouraged to quit regardless of their genetic make-up, she added.