Are you tall or rather on the small size? Such traits may not only depend on our close relatives. They may be an effect of our Neanderthal genes, passed along generations by our earliest ancestors.
Scientists revealed a fact that may surprise some. Even though humanity is constantly evolving, our modern DNA still presents traces from our earliest ancestors. And those Neanderthal genes are more significant that initially believed.
Previous studies showed that they could affect a number of human traits. For example, one’s susceptibility to certain blood or skin conditions. Although the link is small, it still exists.
And a recently released study detected yet another link. Research on the matter was carried out by researchers from the University of Washington in Seattle. Study results were released earlier this week. they were published in the Cell journal.
Available online since February 23rd, the paper was titled as follows. “Impacts of Neanderthal-Introgressed Sequences on the Landscape of Human Gene Expression”. Research on the matter was led by Rajiv McCoy. He is a University of Washington postdoctoral researcher.
And according to the study, our Neanderthal genes make us more susceptible to various specific diseases. But also influence some of our physical traits. Research discovered that the inherited Neanderthal DNA affects the gene expression.
To put it simply, it affects which genes get turned off or on. This event is known as the regulation of gene expression. The phenomenon acts not only on affections but also on common traits. As such, this phenomenon can account for an increased risk of developing lupus or schizophrenia. But also for our being taller or shorter.
For the study, the involved scientists changed their approach. Usually, research looks at a patient’s medical records. Instead, this new research focused on genetic data from the tissues themselves.
And it also paid attention to a specific element. It tried to determine the effects of our still remaining Neanderthal genes. The scientists specifically looked at their relation to the gene sequencing process.
And their research determined that these Neanderthal genes are actually very “pervasive”. Joshua Akey offered additional details on the matter. He is a University of Washington geneticist and also study co-author.
According to Akey, the modern humans carry quite a lot of ancient DNA. The Neanderthal genome is still very much present. And bits and pieces of it are scattered among the modern individuals.
Akey also pointed out an interesting fact. A better understanding of this ancient genome could be very useful. It may help us better understand our genome. And the way in which it functions. This may bring significant benefits in treating genetic diseases. Perhaps even in establishing if a disease is caused by genetic factors.
For the study, the scientists sampled 52 tissues of the human body. Almost none of them expressed a preference for a certain type of gene expression. Be it a Neanderthal or modern human one. But two tissues did express a preference. And they are the brains and the testes.
According to the research, Neanderthal genes are very rarely active in these two tissue types. Which suggest the following, as pointed out by Akey. The brains and testes gene regulation exhibits the most differences between ancient and modern humans.
The influence of the Neanderthal genes on our physical traits also suggests another fact. Our species changed significantly due to ancient interbreeding.
For the study, the scientists used a massive public database. They analyzed 52 different tissues detected across 214 individuals. This massive public database is called the GTEx Project. Or more exactly, the Genotype-Tissue Expression Project.
It offers a database catalog of the RNA levels found in 53 tissues. And these are detected across multiple individuals. The researchers developed their own study design.
One which can be put to various purposes. And which shows a possible new way of researching the Neanderthal DNA. And by looking elsewhere, who knows what else we may find?
This new study may help researchers better understand our shared evolutionary history. And also the functional aspects of genetics. And it may soon be followed by other similar studies from the same or other scientists.
Image Source: Flickr