"Living fossil" coelacanth turned out to be an ancient genetic paradox

Genetic scientist Isaac Yellan of the University of Toronto discovered in the "living fossil" coelacanth an inexplicable and abnormally large number of transposons - the so-called "parasite genes". Initially, Yellan searched a common database for possible precursors of the human gene CGGBP1, a participant in an important genetic regulation procedure. To his surprise, he saw a whole set of varieties of this gene in the coelacanth fish, aka Latimeria chalumnae or coelacanth.

For a long time, coelacanth was considered extinct, and even before the era of the dinosaurs, more than 65 million years ago, until in 1938 it was accidentally caught near South Africa. Comparison with fossil remains showed that the fish has hardly changed over such an impressive period of time. However, modern genetic analysis has puzzled scientists - it looks like the coelacanth has undergone extensive evolution at the genetic level.

It so happens that with horizontal gene transfer, "transposons" appear - genes that can jump to different parts of DNA. This process is chaotic, sometimes they find themselves in a good place and take root, stay there, and in other cases they turn into a hindrance. For this they are compared to viruses. Transposons are found in many species of living things, but due to their nature, they are usually in very small quantities. And the coelacanth had as many as 62.

Moreover, these transposon genes are responsible for coding at least 8 important proteins that are involved, among other things, in gene regulation. Scientists see this as a key to unraveling the history of this outlandish fish - why did not it become extinct over tens of millions of years? Why are her fins more like paws? Why is she close to lungfish and even to humans more than to other inhabitants of the seas? And at the same time, they want to try to understand what role transposons play in evolution in general, and in the development of our species - people - in particular.