Open Access Research article

Characterization of the equine 2'-5' oligoadenylate synthetase 1 (OAS1) and ribonuclease L (RNASEL) innate immunity genes

Jonathan J Rios1, Andrey A Perelygin2, Maureen T Long3, Teri L Lear4, Andrey A Zharkikh5, Margo A Brinton2 and David L Adelson6*

Author Affiliations

1 Department of Animal Science, Texas A&M University, 2471 TAMU, College Station, Texas 77843, USA

2 Biology Department, Georgia State University, 24 Peachtree Center Ave., Atlanta, Georgia 30302, USA

3 College of Veterinary Medicine, University of Florida, 2015 SW 16th Ave., Gainesville, Florida 32608, USA

4 Department of Veterinary Science, University of Kentucky, 108 Maxwell H. Gluck Equine Research Center, Lexington, Kentucky, 40546, USA

5 Bioinformatics Department, Myriad Genetics, Inc., 320 Wakara Way, Salt Lake City, UT, 84108, USA

6 School of Molecular and Biomedical Science, University of Adelaide, SA 5005, Australia

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BMC Genomics 2007, 8:313  doi:10.1186/1471-2164-8-313

Published: 7 September 2007



The mammalian OAS/RNASEL pathway plays an important role in antiviral host defense. A premature stop-codon within the murine Oas1b gene results in the increased susceptibility of mice to a number of flaviviruses, including West Nile virus (WNV). Mutations in either the OAS1 or RNASEL genes may also modulate the outcome of WNV-induced disease or other viral infections in horses. Polymorphisms in the human OAS gene cluster have been previously utilized for case-control analysis of virus-induced disease in humans. No polymorphisms have yet been identified in either the equine OAS1 or RNASEL genes for use in similar case-control studies.


Genomic sequence for equine OAS1 was obtained from a contig assembly generated from a shotgun subclone library of CHORI-241 BAC 100I10. Specific amplification of regions of the OAS1 gene from 13 horses of various breeds identified 33 single nucleotide polymorphisms (SNP) and two microsatellites. RNASEL cDNA sequences were determined for 8 mammals and utilized in a phylogenetic analysis. The chromosomal location of the RNASEL gene was assigned by FISH to ECA5p17-p16 using two selected CHORI-241 BAC clones. The horse genomic RNASEL sequence was assembled. Specific amplification of regions of the RNASEL gene from 13 horses identified 31 SNPs.


In this report, two dinucleotide microsatellites and 64 single nucleotide polymorphisms within the equine OAS1 and RNASEL genes were identified. These polymorphisms are the first to be reported for these genes and will facilitate future case-control studies of horse susceptibility to infectious diseases.