Tiny Shift in Herpesvirus Causes Neurologic Form

Sometimes a small change can make a big difference. Such is the case with equine herpesvirus, according to researchers with Cornell's College of Veterinary Medicine. When it comes to the virus, a change in just one amino acid can make all the difference between triggering a cold or a life-threatening neurological disorder.

The researchers' paper can be found in the Nov. 9 issue of PLoS Pathogens, published by the Public Library of Science. Funding for the study came from the Zweig Fund.

Microbiologists at the school have shown that a single amino acid variation in an enzyme that is part of the DNA copying process of equid herpesvirus type-1 (EHV-1) creates a different type of EHV-1, which causes the neurological disorders in horses. Both types of EHV-1 can also cause abortions.

"There are apparently two distinct pathotypes of EHV-1 out there, and one is more likely than the other to cause the neurological disease. This study provides the ultimate proof," said the paper's Senior Author, Klaus Osterrieder, DVM, DVM Habilitation (German equivalent to a PhD),a professor of virology in the Department of Microbiology and Immunology.

After cloning the genome of the virus obtained from a mare that had both lost a fetus and developed neurological symptoms, the researchers then altered one amino acid in the viral enzyme and rendered the virus unable to cause neurological disease. The amino acid change reduced levels of the virus in the horse's bloodstream, and lower levels of the virus reached the central nervous system. The mutation also made the virus more susceptible to antiviral drugs.

Laura Goodman, who was a graduate student in the Osterrieder laboratory and is now a postdoctoral associate at Cornell's Baker Institute for Animal Health, is the paper's lead author.--Krishna Ramanujan, reprinted with permission from Cornell Chronicle.   

Stay on top of the most recent Horse Health news with FREE weekly newsletters from TheHorse.com. Learn More

Free Newsletters

Sign up for the latest in:

From our partners