Your Neanderthal Genes May Prevent You From Metabolizing Drugs Efficiently

Jan Bartek - AncientPages.com -  Scientists have previously confirmed modern humans and Neanderthals are closely related. In a past study, researchers discovered just 7% of our DNA is unique to modern humans!

According to the study published by Science Advances, humans are not much different from Neanderthals.

"Much of the current genetic variation within humans predates the split, estimated at 520 to 630 thousand years (ka) ago, between the populations that would become modern humans and Neanderthals. The shared genetic variation present in our common ancestral population is still largely present among humans today and was present in Neanderthals up until the time of their extinction.

This phenomenon, which is known as incomplete lineage sorting (ILS), means that any particular human will share many alleles with a Neanderthal that are not shared with some other humans. Therefore, humans often share genetic variation with Neanderthals not by admixture but rather by shared inheritance from a population ancestral to us both," the scientists wrote in their paper.

The results of this study were based on DNA extraction from fossil remains of now-extinct Neanderthals and Denisovans dating back to around 40,000 or 50,000 years ago, as well as from 279 modern people from around the world.

Being closely related to the Neanderthals has certain disadvantages. Recently a team of anthropologists explained their study of the spines of Neanderthals may explain back-related ailments experienced by humans today. The researchers say you can blame the Neanderthals for your lower back pain.

Now, researchers at the Max Planck Institute for Evolutionary Anthropology in Germany and Karolinska Institutet in Sweden have studied two enzymatic variants which eliminate drugs less efficiently and show that these enzyme variants are inherited from Neandertals.

A drug must be administered at the correct dosage to be effective and not harmful. Certain enzymes in the body eliminate drugs, and these enzymes' activity varies between individuals.

Precision medicine aims to customize health care, with treatments tailored to each patient. The hope is that patients are prescribed medications in the right dosage, appropriate to them, based on genetics and other factors. It is well known that genetic variants in the genes encoding enzymes in the cytochrome P450 family affect how efficient these enzymes are.

In the present study, published in The Pharmacogenomics Journal, researchers discovered that two of the most important genetic variants influencing the ability to eliminate drugs are inherited from Neandertals. These variants are carried by twenty percent of present-day Europeans.

The study, led by Hugo Zeberg, a researcher at the Department of Neuroscience and Max Planck Institute for Evolutionary Anthropology, Karolinska Institutet, and Svante Pääbo, Director at the Max Planck Institute for Evolutionary Anthropology, identified a DNA segment inherited from Neandertals, carrying two cytochrome P450 enzymes.

These enzymes eliminate several common drugs such as blood thinner warfarin, antiepileptic phenytoin, cholesterol-lowering drugs statins, and common painkillers such as ibuprofen. The Neandertal variants of the enzymes are generally less efficient at eliminating drugs.

"This is one case where the admixture with Neandertals has a direct impact in the clinic. Otherwise therapeutic doses can be toxic for carriers of the Neandertal gene variant", says Hugo Zeberg.

The study was published in the journal Pharmacogenomics

Written by Jan Bartek - AncientPages.com Staff Writer