1Department of Parasitology, University of Agricultural Science and Veterinary Medicine, Mănăștur Street nr. 3-5, RO-400372 Cluj-Napoca, Romania
2Department of Biological Sciences, Humboldt State University 95521 USA
3Faculty of Biology and Geology, Babes-Bolyai-University Cluj-Napoca, Clinicilor street 5-7, RO-400006 Cluj-Napoca, Romania
4Association for Bird and Nature Protection “Milvus Group”, Targu Mures, 22 Crinului Street, RO-540343
5Molecular Biology Center, Interdisciplinary Research Institute on Bio-Nano-Sciences, Babes-Bolyai University Cluj-Napoca, 42 Treboniu Laurian Street, RO-400271 Cluj-Napoca, Romania
Immune genes of the major histocompatibility complex (MHC) are among the most polymorphic genes in the vertebrate genome. Due to their polymorphic nature, they are often used to assess the adaptive genetic variability of natural populations. This study describes the first molecular characterization of 13 partial MHC class IIB sequences from three European ranid frogs. The utility of previously published primers was expanded by using them to successfully amplify eight exon 2 alleles from Rana arvalis.We also designed a novel primer set that successfully amplified exon 2 from Pelophylax kurtmuelleri. Pelophylax lessonae was also designed as part of this study. Results indicate the presence of one or two class IIB loci in these three species. In R. arvalis, significant evidence of positive selection acting on MHC antigen binding sites was found. Many European ranid populations are experiencing disease-related declines; the newly developed primers can, therefore, be used for further population analyses of native frogs.
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