Polymorphism in innate immune genes in host populations can structure spatial variation in the prevalence of infectious diseases. In Europe, Borrelia afzelii is an important tick-borne pathogen of small mammals including the bank voles (Myodes glareolus). The Toll-like receptor 2 (TLR2) is an innate immune receptor that is important for detecting Borrelia burgdorferi sensu lato pathogens. The TLR2 gene is polymorphic in bank vole populations and is classified into four distinct clusters: C1, C2, C3, and C4. The C2 and C4 clusters versus the C1 and C3 clusters are associated with lower versus higher infection prevalence, respectively. We detected three TLR2 clusters in 487 bank voles from 30 populations in NE Poland: 84.2% of the obtained sequences belonged to the C1 variant, 7.2% to C2, and 8.6% to C3. However, no clear spatial structure of TLR2 clusters among the populations was detected. B. afzelii infection prevalence across all studied individuals was 12.1% and varied from 0 to 37.5% among populations. There were no significant differences in B. afzelii prevalence among voles carrying alleles of different TLR2 clusters, or between individuals belonging to two mtDNA lineages. Most infected individuals were adults, and males were infected more often than females. There was no significant relationship between the prevalence of TLR2 clusters in the vole populations and climatic and environmental factors within the study area. We therefore could not confirm an adaptive role of the TLR2 C2 alleles in reducing B. afzelii infection prevalence in bank voles.

中文翻译：

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波兰东北部银行田鼠种群中TLR2的多态性与非洲疏螺旋体的感染率无关

宿主种群中先天免疫基因的多态性可以构成传染病患病率的空间变异。在欧洲，非洲疏螺旋体是小型哺乳动物的重要tick传播病原体，包括堤鼠（Myodes glareolus）。所述Toll样受体2（TLR2）是先天性免疫受体是用于检测重要莱姆病螺旋体意义上拉托病原体。TLR2基因在银行田鼠种群中是多态的，分为四个不同的簇：C1，C2，C3和C4。C2和C4集群相对于C1和C3集群分别与较低的感染率相对较高的感染率相关。我们在波兰东北部30个种群的487个库田鼠中检测到3个TLR2簇：获得的序列的84.2％属于C1变体，7.2％属于C2和8.6％属于C3。但是，在人群中未检测到TLR2簇的明确空间结构。在所有研究的个体中，Afzelii感染率均为12.1％，在人群中从0到37.5％不等。A.fzelii B.没有显着差异在携带不同TLR2簇等位基因的田鼠之间或在属于两个mtDNA谱系的个体之间流行。大多数感染者是成年人，男性感染率高于女性。在田鼠种群中TLR2簇的流行与研究区域内的气候和环境因素之间没有显着关系。因此，我们无法确定TLR2 C2等位基因在降低银行田鼠中的Afzelii感染率中的适应性作用。