If you’re a smoker, you can blame the Neanderthal DNA within you for your inability to stop smoking. You can also blame Neanderthal DNA, whether fairly or not, on your type 2 diabetes, among other immune-system related diseases. If you have problems giving up smoking, or if you have type 2 diabetes, biliary cirrhosis, Crohn’s disease, or lupus, it could be that your Neanderthal DNA is attempting to reassert itself down the ages, according to a study in the Science journal.
Though only about 20 percent of the original genome of Neanderthals has survived and been passed down to modern humans, that small percentage is more persistent and influential that was previously thought. According to one of the authors of the study, Joshua Akey, Ph.D., an associate professor at the University of Washington, through interbreeding, Neanderthal DNA has “been passed on from generation to generation.”
It’s been known for some time now that Neanderthals and humans interbred, but what was unclear was exactly how much Neanderthal DNA survived and has been passed down to people living today. Joshua Akey and grad student Benjamin Vernot sought to determine the answer to this very question, i.e., to discover exactly how much DNA from Homo neanderthalensis is in our genetic make-ups.
My one percent of Neanderthal DNA may be different from yours
Akey and Vernot discovered that most non-African Europeans have around 1-2 percent of Neanderthal genome in them, but the one to two or three percent and how it affects modern humans might be very different from one person to the next.
That relatively small percent might be useful in determining why some of us develop certain diseases while others don’t, or even answer the question about why some humans have a much more difficult time at giving up smoking than others. The study’s findings might even help you determine if the symptoms that you have match up with a disease which Neanderthals were possibly quite susceptible to getting.
According to Akey, there are some genome parts which contain “too much of the Neanderthal” to be chance. Akey and Vernot discovered that most people inherited about 1 to 3 percent of their genome from Neanderthals, but “my 1 percent may be different than your 1 percent,” Akey explained.
Add up the different remnants, and about 20 percent of the overall Neanderthal genome survived. Although knowing that doesn’t mean we know exactly which traits the DNA accounts for, we do have some insight. According to Akey, conducting the type of research that he and his fellow researcher, Vernot, do allows people to study about certain subjects like ancient DNA and fossils without having either the DNA nor the micrometers with them. You can also learn more about the interactions between Neanderthals and humans.
Neanderthal DNA within us can be considered to be both a blessing and a curse. Much of the Neanderthal DNA that is still left within modern-day humans is related to immune function and behavior traits, like the ability to stop smoking. Perhaps having these traits will be eventually found to be a help in preventing other, worse ailments from manifesting themselves, much in the manner that sickle cell anemia helps some people who develop malaria.
Written by: Douglas Cobb