Genes to blame for difficulty in quitting

A new study shows some smokers have a genetic factor which makes it more difficult to quit smoking.  Smokers who have an abundance of "mu opioid receptors" (MOR) in their brain, are more likely to relapse because their brains find nicotine more rewarding. PET scans were used to show that smokers with excess MOR's had different genetic factors than smokers with less MOR's.
When nicotine fits into these receptors, a flood of reinforcing neurotransmitters are released in the survival and emotional parts of the brain. Humans feel compelled to repeat behaviors that release these "I feel good" neurotransmitters. For smokers, this means, their brain will want to repeat the behavior of smoking.

This research ties our genes to our brain structure to our behavior. Besides leading to new treatments for cessation, hopefully, more people will understand that smoking is not just a bad habit, nor is it a choice, but a physical addiction where smokers need treatment and support to be successful at becoming smoke-free.