Using thousands of chimpanzee fecal samples, researchers created the first genome diversity catalog of endangered chimpanzees in the wild The catalogue allows them to link confiscated chimpanzees to their country of origin in order to curb the illegal animal trade.
According to a report in the Journal of cell genomics today (june1,2022), scientists have made the first catalog of genome diversity of Wild Endangered chimpanzees. The catalogue includes 828 chimpanzee samples from its entire range, providing a detailed reconstruction of chimpanzee population structure and fine patterns of isolation, migration and connectivity. Using this information, the researchers designed a method to link the confiscated chimpanzees with their sources within about 100 kilometers. The purpose is to support efforts to combat the illegal trade of chimpanzees and related products.
The researchers said that this work would not have been possible without the coordinated sampling of thousands of chimpanzee fecal samples in 48 locations by the Pan African program (panaf) and the efforts made over the years to develop methods and strategies for effectively retrieving and enriching the proportion of host DNA in fecal samples. Fecal samples pose many technical challenges because they contain only a small amount of degraded chimpanzee DNA, but they also have the advantage of studying endangered species because they can be widely collected with minimal interference to animals. These methods can now be used to study many other endangered primates and other species.
Because the fossil record and ancient DNA of chimpanzees are limited, the only way to reconstruct their past is through living research. Scientists acknowledge that there are four chimpanzee subspecies, but there have been questions about their relationship. It has been a long-term question about how closely these subspecies are related. In order to explore these issues in the new study, researchers retrieved some genomic information from more than 800 non-invasive collected wild chimpanzee feces samples in the current chimpanzee distribution area. They focused on chromosome 21, the smallest continuous nuclear sequence in the chimpanzee genome, and also the source of a large amount of genome sequence data used to infer the population structure of chimpanzees.
Researchers found about 50% more new genetic variants on chromosome 21 than in previous studies. Relevant data sets have become the key to understanding the recent and past gene flow between chimpanzees. In addition, it enables us to describe whether the population has been isolated recently, or whether there is an isolation caused by a historical event. By describing the genomic characteristics of each community or population, researchers have also created a map that links genomic information with geographical location so that researchers can understand the situation of each population.