Twilight Zone. Scientists have discovered new tiny genes that appeared in human DNA
send to Telegram
share on Facebook
send to Viber
send to Messenger
Researchers suggest they are proof that we are still evolving in ways we never imagined.
Millions of years ago, we parted ways with our primate cousins, but we continue to evolve to this day, and scientists believe that this is happening more actively than we might have previously imagined, writes Science Alert.
This project began back in 2017, when scientists from the Alexander Flemming Biomedical Research Center (BSRC Flemming) in Greece and Trinity College Dublin (Ireland) became interested in the evolution of new genes and the mechanisms of their occurrence. Over time, the project was frozen until a new study was published in 2020, which prompted the researchers to resume their search.
U Focus. Technology has its own Telegram channel. Subscribe so you don't miss the latest and exciting news from the world of science!
In 2020, researchers at the University of California, San Francisco cataloged a set of microproteins that are produced by junk DNA. In essence, they created an ancestral genetic tree to compare these tiny genes with those of 99 other vertebrate species. Scientists have found that some of them can be traced back to the most ancient mammals, while others seem to have appeared only recently. At the same time, two of them appeared after the separation of people and chimpanzees.
According to Nikolaos Vakirlis, an evolutionary geneticist at BSRC Flemming in Greece, this intrigued him and he decided to resume his research. Scientists have focused on identifying and studying instances in the human lineage of small proteins that evolved from previously non-coding sequences and acquired functions either immediately or shortly thereafter.
Microproteins are known to perform a very wide range of functions : from helping to regulate the expression of other genes, to joining forces with larger proteins. It is curious that while some microproteins perform very important biological tasks, others are essentially useless.
According to Trinity College geneticist Aoife McLeesacht, the main problem is that they are difficult to detect and understand whether they make biological sense, which makes research very difficult.
During the study, scientists found that one gene, which plays an important role in building the tissue of our heart, appeared when the common ancestor of chimpanzees and humans diverged from the gorilla.
After that, scientists investigated the function of the sequences in cells grown in the laboratory—they removed the genes one by one and observed. As a result, in fifty cell cultures, scientists found growth defects – in fact, this means that these missing sections of DNA play an important role in maintaining the functioning of our body.
In addition, scientists have also identified variants associated with diseases. For example, the presence of these random mutations in one position of the DNA base can be associated with muscular dystrophy, retinitis pigmentosa, and Alazami syndrome. However, more research is needed to understand this relationship.
Scientists believe that the results of this study may further understand the extent of biological changes that humans have undergone as a result of natural selection. In addition, researchers hope to further understand how new genes are spontaneously created in “junk DNA”.
According to McLisacht, if he and his colleagues are right, then there are much more functionally important things hidden in the human genome, which we are not yet familiar with.