[Genetic Polymophism and Evolution of SRPN14 Gene in Anopheles sinensis (Diptera : Culicidae)].

To identify and locate the serine protease inhibitor 14 (SRPN14) gene of Anopheles sinensis, and analyze its genetic polymorphism among populations as well as the selective pressure during evolution.Primers were designed based on the genomic sequencing data of An. sinensis, and PCR amplification system for the SRPN14 gene was established. The chromosomal location of SRPN14 gene was determined by fluorescence in situ hybridization. The SRPN14 gene of An. sinensis populations collected from 18 sampling sites in 12 provinces (municipality) was sequenced, its genetic variations within and among populations calculated, and the selective pressure during adaptive evolution evaluated.The amplified part of the SRPN14 gene of An. sinensis was 429 bp in length, and had 77%(nt) and 88% (aa)similarities with An. gambiae. The SRPN14 gene located on 2L: 23C of salivary gland chromosomes of An. sinensis. The sequences of 411 individuals from 13 An. sinensis populations were analyzed. In the 411 individuals, the total number of alleles of the SRPN14 gene was 204, among which 51 (25.00% ) showed inter-population consistency. The ranges of SRPN14 allel number and genetic polymorphism were from 11 (Liaoning) to 33 (Chongqing), and from 0.008 (Liaoning) to 0.024 (Hainan), respectively. AMOVA result showed that genetic divergence within populations was significantly higher than that among populations; variation within populations was 95.79% of the total variation. The genetic divergence among populations was small, with FST value of 0.042. The number of synonymous substitutions in SRPN14 was significantly higher than that of non-synonymous substitutions sites, and ω was less than 1 in all populations.Genetic polymorphism occurs in SRPN14 gene of An. sinensis populations, and its evolution is under the negative selective pressure.