As breeding season approaches, mare owners who plan to book stallions in hope of healthy 2011 foals need to be aware of new developments in genetic research. The Arabian breed is one that has had some particularly positive developments in 2010: Cornell University researchers have identified the mutated gene that causes Lavender Foal Syndrome (LFS).
Furthermore, they have developed a simple molecular assay to test for either carriers of LFS or foals afflicted with the syndrome. This simple, non-invasive test, which is available by mail through the New York State Veterinary Diagnostic Laboratory at Cornell, will enable breeders to avoid carrier-to- carrier matings that can produce LFS foals.
Drs. Douglas Antczak and Samantha Brooks and their staff collaborated on this project. Their work, funded in part by the Morris Animal Foundation, was reported in the journal PLoS Genetics in April 2010. The availability of the DNA test was assisted by funding from the Arabian Horse Foundation.
LFS is an important inherited disease of Egyptian Arabian horses and their descendants and is named for the unusual coat color of affected foals. In addition to other symptoms, the foals are unable to stand or lie on their stomachs and often suffer seizures. It causes a complex neurological condition that is always lethal shortly after birth.
The disease is classified as an autosomal recessive condition, which means that horses carrying one copy of the mutant gene appear normal. Only horses that carry two copies of the mutant gene (one from each parent) are affected. Researchers in the laboratories of Drs. Brooks and Antczak have identified the mutated gene (myosin Va) that causes the disease and developed a simple molecular assay that can be used as a diagnostic test to determine carrier status.
According to the Arabian Horse Foundation, LFS research has been limited in large part by the lack of available affected foal samples for organized research projects and by very limited funding. But, in 2008, the research landscape changed and Cornell, in conjunction with the Foundation, initiated a new study on LFS to locate the mutation responsible and develop a direct DNA test.
Genetic testing for Arabian horses is discussed on the website of the Arabian Horse Foundation, where complete instructions for preparing hair samples for the LFS test to be sent to Cornell are available.
Web address for reading or downloading the complete research article: http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1000909