Low Level of Resistance to Anticoagulant Rodenticides in the Vkorc1 Gene in House Mice (Mus musculus) and Norway Rats (Rattus norvegicus) in Russia

Genetic resistance to anticoagulants caused by mutations in the Vkorc1 gene of the most invasive rodent species-Norway rats and house mice, has not been studied in Russia. We analyzed the variability of the Vkorc1 gene in house mice and Norway rats in various settlements of Russia, and identified mutations responsible for resistance to rodenticides. Two exons of the Vkorc1 gene were analyzed in 71 Norway rats from four cities (Moscow, Tyumen, Chita, Rostov-on-Don) and 108 house mice from cities and small settlements (Moscow region, Tormosin, Nizhny Tsasuchei). Three Norway rats (15.8% of the studied individuals) in Moscow have a heterozygous state the Tyr139Ser mutation, which is responsible for resistance. House mice were not found to have mutations in the Vkorc1 gene responsible for resistance to anticoagulants of the first and second generation in the Leu128Ser and Tyr139Cys positions located in the third exon. However, in cities in the first exon, we identified two heterozygous mutations have not be described previously in the scientific literature: Lys58Arg and Ser31Trp. In Russia, the genetic resistance to rodenticides in settlements in the populations of house mice and Norway rats is significantly lower than in Western Europe.