ARS Scientists Develop New Genetic Test for OPP

Researchers from the US Department of Agriculture developed a genetic test for identifying animals with high risk of ovine progressive pneumonia (OPP). OPP is an incurable disease of sheep worldwide. Signs of infection include less productivity, pneumonia, lameness, and "hard bag" syndrome, which causes udders to become hard and produce less milk.

ARS scientists conducted a genome-wide study and discovered that the gene TMEM154 influences the susceptibility of sheep to OPP virus. There are three major forms of the gene present in 97 percent of sheep tested. The two types (halotypes 2 and 3) were strongly associated with OPP virus infection and considered as highly-susceptible forms of the gene. Only one copy of either types was required to increase the risk for OPP virus infection, and ewes with two copies of haplotype 1 were significantly less likely to be infected.

The genetic test is commercially available for producers to detect sheep that are genetically less susceptible to OPP virus and thus reduce the risk of animals being infected, and select breeding stock with low-risk genetic factors leading to less prevalence of the virus in flocks.

Read more at http://www.ars.usda.gov/is/pr/2013/130617.htm.