It is quite fitting that almost 150 years to the day that Charles Darwin’s seminal work On the Origin of Species was published, scientists around the world proposed the creation of a genome zoo; a project called Genome 10K aimed at uncovering the origins of 10,000 vertebrate species by genome sequencing – or mapping their genetic material
One of the 68 scientists pivotal to this project is Dr Emma Teeling, UCD School of Biology and Environmental Science, an extraordinary scientist with a PhD in molecular phylogenetics and whose worldrenowned expertise on bats led to her being chosen.
Through Darwin’s work and all scientists that have followed in his wake, we have experienced a paradigm shift, a world where knowledge of natural selection and evolution has deepened and where disease and immunity can be better explained by understanding our genes, what they contain, and why they are different or similar to other species.
Scientists like Teeling are looking at Darwin’s theories on a molecular level.
“The most challenging intellectual problem in biology for this century will be the reconstruction of our biological past so we can understand how complex organisms such as ourselves evolved,” said Sydney Brenner, pioneering geneticist, Nobel Laureate and one of the authors on the Genome 10K paper.
Teeling is well placed to tackle the Genome 10K undertaking. Having spent the past ten years of her life looking at the evolution of mammals, focusing specifically on bats, she was one of the co-authors on a paper aiming to uncover the bat evolutionary tree, which was published in Science in 2005.
“This was essentially a spring board into being considered an expert in bat comparative genomics. I understood the bat phylogenetic tree, I knew which taxa were important for sequencing from a comparative genomics point of view, and also I had access to a sizeable tissue collection and knew collaborators with large tissue collections of their own,” explained Teeling.
In April 2009 at a three-day meeting at the University of California, Santa Cruz, Teeling and other vertebrate experts met to discuss Genome 10K. Gathered in one room were world authorities on everything from rodents and primates to whales and armadillos.
“One of the reasons they picked bats was that they account for one fifth of living mammals but they are also very, very different: when you think about it, their genome must be so startlingly different because they are mammals but they can fly, they live for an incredibly long time and they use echolocation,” explains Teeling.
Despite these differences bats, as mammals, are related to us yet they have small genomes, making it easier to study genome limits, so the study of their DNA has wide-ranging implications beyond their own species.
While the Human Genome Project was completed in 2003 after 13 years’ work, the research being undertaken by Teeling and her fellow scientists is ground-breaking, as it involves pushing the boundaries of gene technology with next generation sequencers.
“One of the reasons the Genome 10K project is so unusual is that it moves sequencing technology forward to a new level of discovery.”
“If we get the impetus and the funding to push it forward, the technology will exist in the next three years.”
Part of the work Teeling carries out at the BatLab in UCD is akin to piecing together a huge jigsaw puzzle without seeing the picture on the box, she says: “When sequencing a genome you take, for example, three billion base pairs of DNA – a big long string of A, T, C and G – and you randomly chop it up into tiny fragments that are 76 base pairs long: you have to try and piece these all together.
All this work is being carried out, explains Teeling, because it reveals fascinating new information about what makes one animal different from the next: “It is the parts of the genome that are different that makes a species unique, for example parts of the genome that will allow an animal to respond to certain changes in their environment such as climate change or disease”.
“When we look at every single base pair in a genome and see how it changes over time in response to the evolutionary challenges that all of the vertebrate ancestors were faced with: what does it take to be a bird? What does it take to be a fish? What does it take to be human and why are we so different to everything else. Or are we really that different?”
“I really think that we will uncover how life evolved by doing this. I’m sure we’ll also find that things are an awful lot trickier than we think. Perhaps there will be more to the evolution of life than the genome alone but this will not be known until all of these genomes are sequenced.”
When Genome 10K is completed, Teeling and her colleagues will have genetically mapped one sixth of all living vertebrates in a science project unprecedented in both its size and ambition.
Specifically at the BatLab, Teeling is interested in the plethora of interesting questions that can be answered by studying how bats evolved. She talks about the wealth of information in the bat genome, especially their extraordinarily long lifespan that points to natural immunity evolved over time.
“What is different about the bat genome in comparison to others that they have longevity and can resist certain diseases? If you want to know best how to fight a disease you study something that already does.”
“The Human Genome Project was unprecedented but Genome 10K is the next step. Because of this our lives will be very different in the next five to ten years, as it will make personal genomics a very real thing, where you can find out your predisposition to certain diseases amongst other things,” explains Teeling.
“I’ve told my first year medical students that in the near future they will be dealing with this as doctors; they will be undertaking much more genetic testing or screening.”
Thanks to the work of Teeling and the numerous other scientists involved, Genome 10K won’t simply give us insight into bats and other mammals, it will bring us closer to ourselves both as a species and on a personal level.