The critically endangered Gray Gorilla has recently lost its genetic diversity and is multiplying damaging mutations. This was the conclusion of an international research team that sequenced 11 genomes of East Gorilla samples collected up to 100 years ago and compared them to genomes of present-day individuals. The results are now published in Current Biology .
Many wildlife declined in the last century, and scientists have long worried that this decline has led to genetic diversity, increased inbreeding, and an accumulation of damaging mutations. Although this could increase the risk of extinction in endangered species, the study of the recent changes in genetic viability was difficult. In a new study, a team led by scientists from the University of Uppsala and the Swedish Museum of Natural History has used specimens stored in museum collections to analyze changes in the eastern gorilla genomes over the last 1
"We Found Genetic Diversity Gray's gorilla has already seen a significant decline after just a few generations," says Tom van der Valk, a doctoral student at Uppsala University in Sweden.
Gray gorillas are found in the Democratic Republic of the Congo and have yielded in 80 percent in recent decades due to poaching and habitat destruction. The results of the comparison of historical and modern genomes show that this decline has led to increased inbreeding and a loss of genetic variation. This, in turn, means that Gray's gorillas are likely to be less able to adapt to future disease outbreaks and changes in their environment. In addition, scientists identified several mutations that are likely to be harmful and have become more prevalent in the last 4-5 generations due to population decline. However, in the closely related mountain gorilla, the scientists did not detect any significant genetic changes, suggesting that their genetic survival has remained stable over the last 100 years.
"This recent increase in damaging mutations really underscores the need for The gray gorillas are causing a progressive decline in population," says Love Dalén of the Swedish Museum of Natural History.
Some of the potentially harmful mutations that occur more frequently have been found in genes that influence disease resistance and male fertility. In addition, the researchers identified mutations that lead to loss of function in genes associated with the development of fingers and toes, which probably explains why today's gorillas have sometimes fused digits.
"Our study shows that historical museum pieces represent a unique source of observation of recent changes in the genetic status of endangered species," says Katerina Guschanski of Uppsala University.
Interestingly, the reason why Gray's gorillas are more affected than mountain gorillas in their deeper history. While Gray's gorillas recorded a significant increase between 5,000 and 10,000 years ago, mountain gorillas have been rare for several thousand years. This long-term low population may have allowed natural selection to remove harmful mutations before the number of mountain gorillas began to decline in the 20th century.
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