Microsatellite variation among diverging populations of Dermacentor Reticulatus

Abstract

Dermacentor reticulatus is the second most reported tick species after Ixodes ricinus in Europe. Geographic distribution of these ticks is fragmented. Five microsatellite loci were assayed for 23 populations (Latvia, Lithuania, Eastern and Western Poland, Germany, Czech Republic, Slovakia, Croatia, Spain and Ukraine) from three regions (Western-, Central- and Nors-Eastern Europe) spanning the range of distribution, and the levels and distribution of genetic variation were estimated. A total 232 ticks were investigated. Results of analysis showed that most of the molecular variability is contained within populations, and that populations cluster together similarly to known geographic distribution. Genetic drift and limited gene flow was considered to be important in determining the genetic structure within regions. Genetic differentiation FST values ranging from 0.014 to 0.256. Neighbour-joining dendrograms, Bayesian-clustering and PCoA analyses showed two genetic groups of D. reticulatus ticks: Western Europe and Eastern Europe. Eastern Europe group showed no evidence of clusterization according to geographical distribution patterns with low molecular variability between populations. Low genetic differences between Lithuanian, Latvian, Eastern Poland and Slovak populations of D. reticulatus show close relatedness among these populations.