Researchers map animal disease genomes
By MATTHEW WEAVER
PULLMAN, Wash. -- Researchers on the Washington State University campus have spent 15 years mapping genomes for major animal diseases.
The team recently sequenced and published the genome for their 10th animal disease microorganism, Theileria equi, a parasite that causes piroplasmosis in horses, mules, donkeys and zebras.
Other diseases that they've sequenced include several strains of Anaplasma marginale, the most prevalent tick-borne livestock disease worldwide; the cattle disease Babesia bovis and Ehrlichia ruminantum, which causes African heartwater disease in ruminant animals like cows, goats and sheep.
Kelly Brayton, WSU College of Veterinary Medicine associate professor, has been involved with a team of WSU and USDA Agricultural Research Service researchers in mapping the 10 genomes.
The pathogens cost the livestock industry billions of dollars each year, Brayton said.
"These are always poised to become problems," said Charlie Powell, public information officer for WSU's College of Veterinary Medicine.
Some of the pathogens were problems in the past, he noted, but "significant" control mechanisms are now in place.
Brayton said mapping the genomes allows researchers to search for vaccines or find genes involved in an organism's development.
"I think the easy vaccines have been made, they're kind of done," Brayton said. "The ones that are left to do are organisms that are more difficult, tricky -- wily little characters."
Most organisms can invade a host animal's immune system. Having the genome allows researchers to determine how they do that, Brayton said.
The team must grow the bacteria to map the genome. It takes more than a month to get the data, she said.
"You get a million sequence reads and now you have to assemble all of that together," she said. "You have to be confident you've done it correctly."
The researchers use a variety of genome sequencing machines. Newer sequencers are faster and deliver more data at a lower cost.
Brayton said the team will continue its work. There are always more pathogens, she said.
"As soon as you get one genome, you need another," she said.