Two new livestock gene libraries developed by University of Missouri (MU) researchers may help scientists around the world identify critical genes in cattle and swine.

MU research teams have worked on the MU Swine Genome and the MU Bovine Genome projects since 2000 and 2003, respectively. The goal of both projects is to identify all genes that play a role in regulating reproduction.

“The female reproductive system undergoes tremendous remodeling during pregnancy,” says Randy Prather, MU animal scientist. “During the first week of swine embryonic development alone, thousands of genes change. Some turn on, some turn off, and some change their level of expression.”

To catalog these changes, the researchers collected reproductive tissues at each stage of reproductive development and sequenced the genes that were turned on, creating expression sequence tag libraries. Scientists use these libraries to see how genes change during the reproductive cycle.

“In swine, we identified about 15,000 genes that are involved in reproduction, and about 30% of them weren’t in any database before,” explains Prather. “While the bovine project is not yet complete, we’re expecting a similar number.”

About 30% of mammalian embryos never reach maturity. The gene libraries can help identify which genes are responsible for the losses and help scientists select against them.

“We slaughter about 100 million hogs a year in the U.S.,” points out Prather. “Even improving reproduction by a few percent means millions more animals can be produced.”

The libraries allow scientists to study all of the genes at one time, instead of just a few. For more details, contact Prather at (573) 882-2980 or go to the respective sites: MU swine genome project: http://genome.rnet.missouri.edu/Swine/; MU bovine genome project: http://genome.rnet.missouri.edu/Bovine/.