Tracing the source of human illness

While trying to cure diseases that have been for centuries, scientists are also interested in a big question that has not been answered yet: Where does human illness come from? Answering this question is the goal targeted by scientists at the University of Pretoria, South Africa.

Clues from " human cradle"

Previously, talking about the origins of modern humans, scientists often thought of the time when humans began to tame wild animals and at the beginning of the urban process into the Neolithic Era - about 12,000 years ago. Therefore, studies on the origin of the disease often focus on animals and habitats outside Africa.

However, Dr. Charlotte Houldcroft - anthropologist, Cambridge University and Dr. Simon Underdown - expert on human evolution, Oxford Brookes University (UK) - after collecting and analyzing disease patterns products and DNA from ancient bones have shown that: There are many infectious diseases that "coexist with human evolution, dating back more than 10,000 to a million years ago". Many scientists have begun to believe that tropical diseases have long played an important role in human evolution.

Riaan Rifkin scientist in the archaeological area in Africa.(Photo: Riaan Rifkin).

Prehistoric archaeologist Riaan Rifkin - University of Pretoria, South Africa - said that the African region, sub-Saharan - the cradle of modern humans, may be the place to find important evidence of susceptibility. of prehistoric residents who have settled in this land for more than 150,000 years.

"Although the groups of people living by hunting and gathering do not carry disease sprouts such as measles or flu, modern vector pathogens have been proven to have originated during the Pleistocene period," Rifkin said.

Explaining this, Rifkin said: "We all know that nearly 80% of prehistoric people who live on hunting and gathering have died of illness when they are not yet of reproductive age. These diseases have created conditions for prehistoric people to formulate effective mechanisms for infection prevention. " The current pathogen in addition to helping to form human biological immune system is also considered a selective factor that helps develop "behavioral immune system" (can be understood as the psychological mechanism that allows Body organs recognize hazards and trigger reactions to stop them.

Journey to decipher the big mystery

Prior to Rifkin and colleagues, historical evidence of prehistoric pathogens provided valuable information, making it easier for scientists to classify and outline the geographical origin of the disease. However, in order to get a complete map of human disease origin, we lacked analysis of insect vectors, intestinal parasites and DNA prehistoric pathogens from prehistoric times in Africa.

Rifkin and colleagues are analyzing archaeological samples related to the activities of prehistoric people as well as their whereabouts in the cave. They are also analyzing fossils from the Middle Stone Age and the Late Stone Age at archaeological sites dating from 150,000 to 1,500 years ago. These areas have full evidence of the behavior of modern people. South African archaeologists have found the first examples of abstract and symbolic art here. These evidences show that our ancestors used fire to create stone tools and produced some of the oldest personal ornaments and cosmetics ever known.

They focus on three main sources of information, such as insect-induced disease vectors (fleas, lice and ticks), intestinal parasites and bacterial pathogens at the macro, micro level. tissue and molecule.

In the laboratory, after examining the vectors and parasitic eggs, scientists used a biomolecule approach to look for prehistoric pathogens. With the help of the Center for Microbiology and Gene Ecology, Rifkin hopes they can get encouraging results with prehistoric specimens. They will then use DNA sequencing methods to search for pathogenous viruses, bacteria and other eukaryotic microorganisms in the samples found to answer the question: Which pathogens Native to Africa? How are they scattered? .

The ambition of Rifkin and his colleagues after decoding the disease vector and pathogen gene to understand the origin, life cycle and prevalence of pre-existing diseases for prehistoric humans in Africa is DNA comparison chart. of modern and prehistoric pathogens. Prehistoric pathogens may help produce new vaccines and the results of their research can help find modern pathogens that are associated with ancient pathogens, thereby studying ways to treat those. modern disease.