[Study on allele mutation of in Zichuan District, Zibo City, Shandong Province].

Objective: To study the seasonal dynamics of and the distribution of knockdown resistance () gene related sodium channel gene polymorphism in Zichuan District, Zibo City, Shandong Province.

Methods: mosquitoes were collected in Zichuan District during the peak period of mosquito vector activity from 2017 to 2018. The DNA from was extracted, and the genotypes and frequencies of allele mutation were detected by polymerase chain reaction.

Results: Totally 830 mosquitoes belonging to six species, including , , , , , and were collected in this study. The number of accounted for 83.13% in total, with the density of 12.32 per lamp per night. The annual density monitoring curve of showed a bimodal trend, and the peaks were observed in June and September respectively. In this study, five alleles were detected at the 1 014 locus of gene, with TTA (75.71%), TTT (10.00%), CTA (5.71%), TCA (4.29%), and TTC (4.29%). Two nonsynonymous nucleotide mutations were detected at site 1 014 of gene, namely leucine (L1014) mutated to phenylalanine (L1014F) and serine (L1014S). The gene mutation frequency (%) of in Luochun Town and Taihe Town was 10.53% and 40.63%, respectively, and the difference was statistically significant ( 2 = 8.559, = 0.003).

Conclusions: is the dominant mosquito species in Zichuan District. In addition, two novel mutations, CTA and TTC, are identified in the voltage-dependent sodium channel gene of . The genotype of in Zichuan area was polymorphic.