Jumping genes helped evolution
Tuesday, 30 August 2011
"[Jumping genes] are an excellent way to throw up new mutations."
Local research theory gives further proof to evolution and may help explain big evolutionary jumps in species.
Murdoch Univeristy Professor Wayne Greene and PhD student Keith Oliver have posited that transposons —also known as jumping genes—have had a larger role in primate and human evolution than is traditionally thought.
Jumping genes are sequences of DNA that have the ability to move to different positions within the genome of a developing organism.
Movement on the genome can cause mutations that may then be expressed in the observable characteristics of the organism.
“Jumping genes confuse the cell during chromosomal replication and cell division which can lead to large scale duplications or deletions of the genome,” Prof Greene says.
“They are an excellent way to throw up new mutations.”
Prof Greene says that he and research partner Keith Oliver were surprised about how much evidence they could find of jumping genes role in evolution.
Their theory cites examples of a large range of traits in humans and primates that transposons are responsible for.
“Visual red-green colour perception, faster brain function, better foetal nutrition in the womb along with a more assertive placenta and better infectious disease resistance are just some of the evolutionary advances brought about by jumping genes,” he says.
Prof Greene says the theory will help strengthen the argument for evolution and may be useful in explaining and understanding the large-scale changes that occur in a species, known as macroevolution.
“You can understand microevolution, small scale changes with a few little mutations here and there, but to make the big jumps in evolution it is really hard to understand without major changes to genomes which jumping genes can facilitate,” he says.
It may also help explain why throughout history some species became extinct while others thrived.
Prof Greene says an abundance of jumping genes can be beneficial to a species because it throws up more mutations helping a species adapt to an ever-changing environment.
“If [organisms] can’t adapt and change to altering environmental conditions the most likely outcome is for the species to become extinct,” he says.
Prof Greene says that their theory follows on from a lot of similar work in the field but was surprised that they are the first to put it all together.
“What we have done is look at the overall picture of what evidence is out there, brought it together and then formalised that information into an hypothesis.”
Previously jumping genes were considered “junk” DNA but Prof Greene hopes his theory may persuade scientists to further research the genes.
Editor's Note: Original news release can be found here.