Unlocking The Secrets Of Evolution

Exactly fifty years ago, Watson and Crick revealed the structure of DNA, unleashing a scientific revolution. On the anniversary of that momentous discovery, the world’s leading science journal, Nature, will publish new and groundbreaking genetic research by Bangor University scientist, Dr. Isabelle Colson. Isabelle is an expert in evolutionary biology, the study of how life evolves, and for 18 months she was an invaluable part of a Manchester-based team studying mutation in yeast – a seemingly simple organism, but one that can shed light on many aspects of evolution. Isabelle’s group were the first scientists ever to see, actually happening, one of the ways yeasts can mutate into new species. On March 6th, Nature will reveal how Isabelle and her colleagues unlocked the secrets of one of evolution’s key mechanisms.

Scientists had long suspected that they knew how yeasts, like other organisms, mutate and evolve into new species – but they’d never seen it in action. Isabelle and her team took a small yeast with a big name, Saccharomyces ‘sensu stricto’, and actually caused it to mutate by shuffling around large chunks of genetic information. This swapping of information, or ‘translocation’, occurs naturally, and by learning how to mimic the process, scientists are closer to understanding how one species changes into another. This is one of the key studies of evolutionary biology, with important practical implications, like understanding how bacteria evolve antibiotic resistance.

So how does the ‘translocation’ lead to new species of yeast? Just as all newspaper stories are made of words, all life on Earth is made of genes – little pieces of genetic information that form the ‘blueprints’ for life. And, just as words naturally come in paragraphs, collections of genes are grouped together into bigger units called chromosomes. When the scientists cause translocation, entire chunks of one chromosome swap
places with chunks of another chromosome, almost like sentences switching place from one paragraph to another. And, just as you would expect that swap to radically change the meaning of the paragraphs in
your newspaper, this genetic translocation dramatically changes the ‘meaning’ of the yeast’s genetic code, even creating new species in the right circumstances.

For years, Isabelle has been passionate about the study of evolution. “When I was 7” she notes, “I wanted to be a palaeontologist. I was obsessed with dinosaurs, and it all started from there.” Having shone a torch into the inner workings of evolution itself, Isabelle would probably agree that she’s come a long way.