Scientists at the LSU AgCenter Aquaculture Research Station have been known for genetic research on farm-raised fish, but that research is evolving into genetics in the biomedical arena.
Terry Tiersch, a researcher at the station, has two National Institutes of Health grants totaling more than $1.5 million that allow him to look at certain fish species to be used in human healthcare.
His work with these two grants involves cryopreservation or the freezing of sperm from zebrafish, swordtails and platyfish to look at preserving the genetic resources of these fish which are a tremendous value in disease research.
“Of these two grants, I’m the principal investigator on a five-year grant, for which we’re doing cryopreservation work for the Zebrafish International Resource Center in Eugene, Oregon,” he said.
Because ZIRC doesn’t have expertise to do this research, Tiersch and fellow researcher Huiping Yang do the work for them and provide them with technology tailored to their needs, which is frozen fish sperm.
“We develop the technology, and they make it available to the research community,” Tiersch said.
The second NIH grant is for the development of storage preservation for platyfish. Both grants have been renewed several times, which shows their importance.
Zebrafish are a powerful biomedical model used around the world because they have the same basic genetics as humans, but are cheaper and easier to work with than mice or monkeys.
Hundreds of thousands of lines of research fish are available, and it is impossible to store and feed them all as live fish. There are more than 20,000 lines of zebrafish alone.
“Some of these lines may hold the cures for cancer -- but we can’t maintain them all. That’s why NIH wants to get them frozen,” Tiersch said.
Without cryopreservation, it would be nearly impossible to study the many lines, largely because each line would need more than one tank.
Instead of having to feed, house and handle live fish, Tiersch is shifting the focus to germplasm and genetic resources, which can be frozen and stored in “straws.”
There’s a multi-billion dollar global industry for frozen cattle sperm and human sperm, Tiersch said. “There will also be a multi-billion dollar global industry for fish sperm.”
The technology is there to move forward with cryopreservation. But first, there has to be market development, safety measures put in place, ownership agreements signed and pricing worked out.
Work on these biomedical fish species is directly transferable to farm-raised or imperiled species.
“We’re involved in improving or managing the genetics of fish and oysters to give benefits to the people who raise those animals; the fish farmers and oyster farmers,” Tiersch said.
Two barriers to the fish genetic research that has been done over the past 50 years include many studies that produce lots of data but have not been extended to the scale that would be useful to hatcheries, and farmers and hatcheries that are unfamiliar with the new technology.
“My approach has always been to get over technological barriers to make research useful to the end user,” said Tiersch.
Fewer than 10 American companies are currently involved in Tiersch’s research, but there is wide interest in this type research worldwide. That may be explained by the U.S. making up only three percent of the world’s production in aquaculture.
“In addition, aquatic animals are the species that is going extinct the fastest,” Tiersch said. “The only work I do overseas is with endangered species.”