Africans are the only people with 100% human DNA-report

In a recent report published by a Harvard researcher, he discovered that Africans are the only race that have 100 percent human DNA while the rest have Neanderthal DNA in them. Various researchers have argued this statement, with a report found which corroborates the Harvard study.
Dr. David Emil Reich, a genetics professor at Harvard, and his team carried out an analysis of the genetic variants of about 846 non-African people. Also, 175 people who live in the sub-Saharan region of Africa were analyzed, and a 50,000-year-old Neanderthal man.
The result shows that nine genetic variants found in humans are associated with specific attributes that can be found in Neanderthals. The same genetic variants found are the same ones responsible for such diseases as lupus, biliary cirrhosis, Crohn’s disease, Type-2 diabetes, and optic disk size.
Dr. David and his team also discovered that this Neanderthal DNA affects how keratin filaments were developed. As opposed to humans, Neanderthals have more keratin filaments than humans making their skin tougher. This enables them to survive in harsh, cold, climates conditions. That DNA was beneficial to human survival in such climates conditions.
A separate research done by Dr. Benjamin Vernot and Dr. Joshua Akey from the University of Washington resulted into the same conclusion after the scientists examined the genetic makeup of 286 East Asians and 379 Europeans.
According to the researchers, Neanderthal skin genes can be found in Europeans and East Asians. On the other hand, the rest of the genes are incompatible with the human genome and they most probably become obsolete. One area of the human genome where the Neanderthal DNA is missing is that which affects the human language and speech.
The Harvard researcher DR. David said that the objective of the research is to understand the analysis of the biological impact on how human and Neanderthal DNA are compatible. It will also help researchers and the scientists on what genes have been preserved and which ones have been rejected through the process of natural selection