The 'PreNeolithic Malaria' project investigates the Paleolithic origin of human genetic traits that confer protections against deadly malarial infections. By applying cutting-edge methods, the project explored the genetics of Central African populations with different subsistence economies, either based prevalently on farming or hunting-gathering. Both groups of populations are known to be affected by genetically inherited blood disorders that confer them a variable level of protection from strong malarial infections, by allowing them to keep the infection at low levels. These blood disorders are caused by different kinds of genetic mutations, which are transmitted from one generation to the other as long as malaria is endemic in the environment where the populations live. Such evolutionary adaptation is linked to a double public health problem: the first is the need for people to survive malarial infections, not yet eradicated in many parts of the world with limited access to medical treatment; the second is caused by the mutations causing blood diseases that are protective from malaria but also can be damaging for the carrier. This scenario is considered as an evolutionary trade-off that allows populations living in malarial endemic areas to survive the infections at the cost of losing the lives of individuals who are affected by severe inherited blood conditions. As many of the populations living in malarial areas are very little studied from a medical genetic perspective, the genetic basis of their inherited blood conditions is also limitedly known. This project serves the double aim of studying in deep the genetic underlying blood disorders in these populations, both known and unknown, and, at the same time, understanding the ultimate evolutionary origin of human adaptation to a deadly parasite (the malarial causal parasite) which has affected our species for thousands of years.
Conclusions of the action: The results so far obtained from the preliminary data analysis suggest a high variation of genetic variants protecting from malaria in hunter-gatherers, some of which are known to be mostly present in populations outside of Africa and differ from those carried by neighboring farmers. As such, my results point to an ancient adaptation to malarial parasites in hunter-gatherers
