Researchers from The University of Utah have discovered the elusive "hybrid inviability gene," which is responsible for the dead or infertile offspring that result when two species of fruit flies mate with each other. Not only does it shed light on the genetic processes that contribute to the formation of new species, but it may also provide help in understanding the development of cancer.
"We knew for decades that something like this gene ought to exist, and our approach finally allowed us to identify it," Nitin Phadnis, principal author of the study, said in a press release. "You call them new species when there are barriers that prevent them from breeding with each other. Identifying these genes and uncovering the molecular basis of hybrid sterility or death is key to understanding how new species evolve and remains one of the big and longstanding questions in biology since Darwin."
The gene, named gfzf, is categorized as a "cell cycle-regulation gene," meaning it is normally involved in the halting of cell division and replication if any mutations or detrimental defects are detected. However, when scientists in this study disabled the gene, they found that it allowed the survival of male hybrids between the two fruit fly species.
The gene may have been favored by natural selection because it helps control the process of jumping genes, which can lead to a disruption of essential genes and cause mutations.
"Even when we are little kids, one of the first things we discover about the world is the tremendous number and diversity of species on Earth," Phadnis said, according to Phys.org. "Speciation is the engine producing that diversity. So understanding speciation has been a longstanding problem, even before the days of Darwin. Now, we finally are able to use technology in creative ways to solve such old, longstanding problems."
The findings were published in the Dec. 18 issue of Science.
