04/01/2009

Coming Soon: Final Map of Whole-Genome Sequence of Catfish

AUBURN, Ala. — As recently as five years ago, Auburn alumni professor of fisheries and allied aquacultures John Liu was convinced it would be 20 to 30 years before the catfish genome project he launched in 1997 would yield the final physical map of the entire catfish genome. “When we have the whole genome sequence of catfish,” he’d say, "I will be old enough to retire."

But major advances in sequencing and computing technology since then have so accelerated research at the Molecular Genetics and Biotechnology Lab in Auburn that Liu, one of the world’s top fish geneticists, now says the finished version of the catfish genome sequence will be unveiled within the next two years.

"And I will not then be even close to retiring," Liu, who also is associate director of the Alabama Ag Experiment Station, says now.

In his genome research, Liu has used the premium “AU Hybrid” catfish that Rex Dunham, a fellow Auburn fisheries scientist who, like Liu, is recognized internationally, developed. By the time Liu and his research team complete the genome sequence, they will have discovered and identified all 28,000 catfish genes, determined the sequence of chemical base pairs that make up catfish DNA and located genes associated with particular traits—in essence, all the biological information needed to build a catfish.

The presentation of the whole catfish genome map, however, will bring the project to a close. In fact, Liu and collaborators—Huseyin Kucuktas, a fisheries research fellow at Auburn, and Geoff Waldbieser with USDA’s Ag Research Service—have just been awarded a $745,000 grant to analyze 24,000 single nucleotide polymorphisms in order to discover DNA sequence variations between different catfish species.

In layman’s terms, that means the scientists will take different lines of catfish that outperform the others in a specific trait—the fastest-growing line, for instance, or the most feed-efficient species, or the one most resistant to disease—and, through the wonders of science and technology, locate in each of the species the precise gene or genes responsible for those traits.

Ultimately, the comprehensive catfish genetic data will allow researchers to develop a catfish that is superior in all traits crucial to catfish producers, and that, of course, is what the whole project is about: offering growers a not only a top-quality, high-yielding catfish but one that is significantly cheaper to produce.

Such improvements are crucial, Liu said, if the U.S. catfish industry is to remain competitive in the world marketplace.

# # #

News from:
OFFICE OF AG COMMUNICATIONS & MARKETING
Auburn University College of Agriculture
Alabama Agricultural Experiment Station
3 COMER HALL, AUBURN UNIVERSITY
AUBURN, AL 36849
334-844-4877 (PHONE) 334-844-5892 (FAX)
AgComm@auburn.edu

Contact: Jamie Creamer, 334-844-2783 or creamjs@auburn.edu