Yesterday I mentioned the “lung cancer gene.” This is interesting stuff to me, and exciting for a potential cure to lung cancer, the No. 1 cancer killer.

Several years ago, researchers isolated a gene mutation that appears to mark whether you are at risk for lung cancer.

One of the most exasperating arguments I’ve ever had with smokers, both in real life and online, is “if smoking causes lung cancer than why don’t all smokers get lung cancer?”

It’s a weak excuse to keep smoking. I remember having that very argument with my mom 30 years ago when my dad died of lung cancer. But, they’re right in that only about 10 percent of smokers ever develop lung cancer. This lung cancer gene mutation could explain why and many other things.

Here’s how it works, keep in mind that 15 percent of the people who get lung cancer (and 20 percent of women who get lung cancer), never smoked a cigarette in their lives. Why do some nonsmokers get lung cancer and most smokers don’t?

It’s been long known that cigarette smoking causes lung cancer by literally screwing up the DNA of the cells in the smoker’s lungs. Why do 10 percent of smokers have their DNA messed up and not all smokers?

In 2008, it was announced that there appeared to be a genetic mutation behind lung cancer. If you have this genetic mutation, you are at increased risk to lung cancer even if you are a non-smoker. I’ve read that your risk is something like 30 to 80 percent higher than a nonsmoker without the gene.

If you have this genetic mutation and you smoke, you are at extreme risk for lung cancer. One article I read long ago (can’t find it now), suggested that your odds of getting lung cancer are 50-50.

If you do not have this mutation, smoke ’em if you got ’em, because you will likely NEVER develop lung cancer … however, this gene mutation has no effect on your chances of getting COPD or heart disease or other kinds of cancer from smoking. So, really, you’re just dodging one out of a potentially large number of bullets.

If you do not have this mutation and do not smoke, your chances of ever getting lung cancer are astronomically low. Unless you’re breathing radioactive isotopes, you don’t even need to worry about it. You’re probably more at risk for being hit by lightning.

This gene might also have something to do with why marijuana smokers do not appear to be at increased risk for lung cancer while cigarette smokers are.

This is where the genetic issue gets even trippier. Not only does there appear to be a gene that makes certain people more susceptible to lung cancer, there also appears to be a gene that also makes some people more susceptible to addiction to nicotine. That could explain why some people can quit smoking while others cannot. It really has nothing to do with willpower. Some extremely strong-willed people simply cannot kick the nicotine, while others can do it and never look back. It might be genetic.  What’s really weird are studies suggesting that the same gene mutation might be responsible for both increasing the risk of lung cancer and the susceptibility to nicotine addiction. Trippy stuff.

How people evolved with these genetic markers triggered by tobacco is beyond me. Tobacco in its current form didn’t even exist until perhaps 150 to 200 years ago. What the North American Indians smoked thousands of years ago is nothing like the tobacco grown today. It’s a mystery.

Anyway, the other exciting part of this is perhaps one day lung cancer will be treated via gene therapy. Already, in this day and age, if you want to pay the money, you can have a gene test done to see if you have this gene mutation. The down side to such a test is maybe some people will say, “hooray, I can smoke all I want now…” which would be a dumb response to such a test. Like I said earlier, you could still lose years off your life through COPD and heart disease by smoking.

Another exciting development of this discovery is scientists are working on a drug to block the gene mutation before it ever develops into cancer.