Genetic mtDNA-CO ? diversity of Aedes albopictus populations in different terrains of Hainan Province.

Objective To explore the genetic diversity of Aedes albopictus populations in plain, hilly, and mountainous areas of Hainan Province, and to analyze the genetic structure of Aedes albopictus populations in different terrain regions of Hainan Province. Methods Aedes albopictus were collected from the plain areas of Sanya and Haikou City, the hills of Danzhou and Tunchang City, and the mountainous areas of Baisha City in Hainan Province. DNA was extracted from a single mosquito and stored in a -80 °C refrigerator for use. Mitochondrial cytochrome C oxidase subunit I (mtDNA-CO I) was amplified by PCR and sequenced. The results were compared on the National Center for Biotechnology Information (NCBI) website, sequence peaks were observed using BioEdit 7.0, genetic diversity parameters were calculated using DnaSP v6, haplotype networks were constructed using PopART 1.7, and analysis of molecular variance (AMOVA) values were calculated using Arlequin to analyze differences between populations. Results A total of 414 mtDNA-CO I sequences were obtained from Aedes albopictus populations in 5 regions, with lengths of 663 bp. All sequences had five mutation sites, with a G+C content of 32.86% and an A+T content of 67.14%, consistent with mitochondrial DNA characteristics. Compared with other populations, the nucleotide diversity of the Danzhou and Tunchang populations in the plain and hilly areas was higher. The average nucleotide differences were higher in the Sanya, Tunchang, and Danzhou populations. Haploid analysis revealed 6 haplotypes, with H02 being the dominant haplotype. The Sanya and Tunchang populations had the highest number of haplotypes, while the Haikou and Sanya populations had exclusive haplotypes. Only the plains populations had unique haplotypes, while the hill and mountainous populations had relatively fewer haplotypes. The neutral results and mismatch distribution map indicated that the population of Aedes albopictus has recently expanded in all regions. The AMOVA value showed that the intra-population differences were greater than the inter-population differences. Conclusions The mtDNA-CO I gene can serve as a molecular marker for studying the genetic diversity of Aedes albopictus populations. The Sanya population in the plain region shows higher genetic diversity, and the two populations in the hilly region also have higher genetic diversity. However, the number of haplotypes is only higher in the Sanya population in the plains and the Danzhou population in the hills. [ABSTRACT FROM AUTHOR]