The discovery of 119 million-year-old selfish genes in yeast has changed the understanding of how parasitic DNA influenced genome evolution

The meiosis driver gene is a selfish gene that is indeed selfish
.
They are present in the genomes of almost all species, including humans, and they unfairly transfer their genetic material to more than half of their offspring, sometimes leading to sterility and reducing the health of
the organism.
Due to their parasitic potential, their lifespan was considered short during evolution, until now
.

A new study by the Stowers Institute of Medical Research, in collaboration with the National Institute of Biological Sciences in Beijing, China, has found a family of selfish genes that has been around for more than 100 million years — 10 times longer than any known driver of meiosis — raising new doubts about established beliefs about how natural selection and evolution handled these threat sequences
.

Associate researcher Dr Sarah Zanders said: "It has always been thought that because these genes are so harmful, they don't stay in the population for long
.
We've just discovered that this isn't true and that genomes can't always get rid of them
.
”

Meiosis drivers are named because they acquire the ability of "driver" genes to propagate throughout the genome, often with negative consequences
.
Natural selection is therefore a major force counteracting selfish genes, favoring the eradication of genetic variants
that restore fertility and the overall health dynamics of the species.

"Natural selection has a limited ability to remove meiosis drivers from populations," Zanders said
.
"Imagine holding soccer team tryouts (natural selection) and recruiting the best players (health-promoting genes).

A driver is a player
who sabotages other players' attempts.
The drivers joined the team, but not because they were good at football
.
”

In a recent study, a team led by researchers in Zanders' lab, Dr.
Mickael De Carvalho and Dr.
Guo-Song Jia, found for the first time that a family of selfish genes called WTF not only thrives in schizoscharomyces pombe, but has been passed on to three unique yeast species that split from schizocharomyces about 119 million years ago
。

"This finding is particularly novel because a family of driver genes thrives at least 10 times
longer than geneticists think it is possible.
"

During meiosis, a special cell division that produces germ cells such as sperm and eggs, the genetic material from a group of chromosomes from both parents has a 50/50 chance of inheritance, or the genetic chance of each germ cell is equal
.

The meiosis driver in yeast is actually a more powerful genetic parasite
.
The WTF gene family is the killer gene for meiosis; Not only do they pass selfish genes on to more than 50% of their offspring, they also destroy germ cells (or spores in yeast)
that don't inherit driver genes.

Natural selection in the genome often saves a species from selfish genes and rendering it useless
by favoring inhibition or inhibition of the genes that drive.
How the WTF gene family evades inhibition is largely due to their rapid mutation rate
.

This persistence has changed our view of how a species can overcome the increase in infertility, which often leads to species extinction
.
It has also changed the way
scientists look for and identify families of selfish genes in different species, including humans.

"Until now, when looking for candidate drivers in the genome, I wouldn't consider 'old' genes as a possibility," Zanders said
.
"Since selfish genes are a major driver of evolution, this new discovery opens the door
to thinking about how drivers can have a lasting, long-term impact on genome evolution.
"

Other authors include Ananya Nidamangala Srinivasa, R.
Blake Billmyre, PhD, Jeffery J.
Lange, PhD, and Ibrahim M.
Sabbarini
.

This research was supported by the National Institutes of Health New Innovator Award (Award: DP2GM132936) and supported by
the Stowers Institute of Medical Research, the Ministry of Science and Technology of China and the Beijing Municipal Government.
Content is the sole responsibility of the author and does not necessarily represent the official views of
NIH.