SNP Marker Discovery in Koala TLR Genes
Jian Cui1, Greta J. Frankham2, Rebecca N. Johnson2, Adam Polkinghorne3, Peter Timms3, Denis O’Meally1, Yuanyuan Cheng1, Katherine Belov1*
1 Faculty of Veterinary Science, University of Sydney, Sydney, NSW, Australia,
2 Australian Museum Research Institute, Australian Museum, Sydney, NSW, Australia,
3 Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
Toll-like receptors (TLRs) play a crucial role in the early defence against invading pathogens, yet our understanding of TLRs in marsupial immunity is limited. Here, we describe the characterisation of nine TLRs from a koala immune tissue transcriptome and one TLR from a draft sequence of the koala genome and the subsequent development of an assay to study genetic diversity in these genes. We surveyed genetic diversity in 20 koalas from New South Wales, Australia and showed that one gene, TLR10 is monomorphic, while the other nine TLR genes have between two and 12 alleles. 40 SNPs (16 non-synonymous) were identified across the ten TLR genes. These markers provide a springboard to future studies on innate immunity in the koala, a species under threat from two major infectious diseases.