When the beluga tissue first arrived at the Genome Sciences Centre, the geneticists gathered around to look. Every day this cancer agency in Vancouver, BC sequences human DNA, studying the mutation of tumors. Human DNA is pedestrian stuff around those hallways, but beluga DNA — now that was something special. And the geneticists were about to do something rather special with the DNA, something that had never been done before. They were going to sequence the beluga’s genome.
In 2000, the White House announced mission accomplished on sequencing the human genome. (Researchers released a more polished draft three years later.) This visionary project took over a decade, cost $2.7 billion and involved 20 universities and hundreds of scientists around the world. But what does sequencing the genome of a species actually involve? And how could it help the beluga whale?
“A decade or so ago we sequenced the human genome and we’ve learnt a lot from that about human biology and human disease. Sequencing the beluga genome ultimately will provide us with lots of tools to learn about the beluga whale as well.”
The process is both massively complex and surprisingly straightforward. The human genome is 3.2 billion base pairs long and sequencing it requires ordering all the nucleotides that make up the DNA double-helix ladder. Each long strand of DNA (called a chromosome) can be thought of as a book containing the recipes (or genes) for building small parts of an individual, while the entire genome is the entire set of books for cooking up the complete human. Or, in this case, the beluga whale.
Some scientific advancements are borne out of tragedy, and unfortunately, this was the case with sequencing the beluga’s genome. In November, 2016 a mother and calf beluga at the Vancouver Aquarium became very sick. In the race to figure out what was causing their illness, the Genome Sciences Centre searched the beluga tissue samples, looking for DNA from pathogens or viruses. They didn’t find any and the Aquarium’s beloved belugas passed away.
“My interest was: can something good come of this?” says Dr. Steven Jones, the Co-Director and Head of Bioinformatics at the Genome Sciences Centre. With enough beluga tissue and a lab full of technicians and high-tech equipment, he realized that they could take the next step in understanding beluga genetics — one that could provide insight to understanding the beluga whale and the challenges this threatened animal faces in the wild.
“We were able to involve some extra cutting-edge technology and tools that actually makes the beluga genome now one of the most complete mammalian genomes that we have on record in the scientific world.”
In the nearly twenty years since the Human Genome Project concluded, researchers have made discoveries about our species in surprising areas. For instance, we’ve uncovered more information about the origins and migration routes of the modern human and found that human DNA has far fewer, and more sophisticated, genes than expected.
The beluga joins the killer whale, the bottlenose dolphin and the minke whale, and others, among the ranks of fully sequenced cetaceans to date.
Sequencing a species’ genome for the first time is very different today, compared to in the 1990s’. The process takes months, rather than years, and thousands of dollars, rather than billions. With advances in technology, researchers are publishing new genomes each month. They’re even being used to commemorate anniversaries. In 2017, the University of Toronto sequenced the beaver’s genome for Canada’s 150th anniversary. A UK genomics centre held a Twitter contest (#25genomes), crowdsourcing new species to sequence for its 25th anniversary. The beluga now joins the killer whale, the bottlenose dolphin and the minke whale, and others, among the ranks of fully sequenced cetaceans to date.
“This is a nice example where the captive population will be generating a genomic resource that is going to be able to help the wild populations, in understanding the genetic diversity for example.”
With the beluga’s complete genetic information now published, the questions we can ask are suddenly wide open. It could help explain how the beluga evolved a dorsal fin or how it stores its fat in dense blubber. It could reveal new insight into how low genetic diversity is affecting the struggling Cook Inlet and St. Lawrence Estuary populations. Or it could help save a sick beluga in the future, struggling with an unknown illness.