文献类型： 外文期刊

作者： Gui, Zheng ¹ ; Cai, Hao ¹ ; Qi, Dong-Dong ³ ; Zhang, Shun ¹ ; Fu, Shao-Yin ⁴ ; Yu, Jing-Feng ⁵ ; Si, Xiao-Yan ⁶ ; Cai, Ting ¹ ; Mao, Rui ¹ ;

作者机构： 1.Univ Chinese Acad Sci, Hwa Mei Hosp, Key Lab Diag & Treatment Digest Syst Tumors Zheji, Ningbo 315010, Peoples R China

2.Univ Chinese Acad Sci, Ningbo Inst Life & Hlth Ind, Ningbo 315010, Peoples R China

3.Hulunbuir Mental Hlth Ctr, Hulunbuir 022150, Inner Mongolia, Peoples R China

4.Inner Mongolia Acad Agr & Anim Husb Sci, Hohhot 010110, Peoples R China

5.Inner Mongolia Med Univ, Dept Parasitol, Hohhot 010110, Inner Mongolia, Peoples R China

6.Inner Mongolia Ctr Dis Control & Prevent, Hohhot 010110, Inner Mongolia, Peoples R China

关键词： Rickettsia; gltA; ompA; Rickettsia identification; Genetic diversity

期刊名称：PARASITES & VECTORS （ 影响因子：4.047； 五年影响因子：4.223 ）

ISSN： 1756-3305

年卷期： 2022 年 15 卷 1 期

页码：

收录情况： SCI

摘要： Background: The genus Rickettsia contains the lineages spotted fever group (SFG), typhus group (TG), and transitional group (TRG). The spotted fever group Rickettsia (SFGR) is transmitted by ticks. The tick species Dermacentor nuttalli is considered the main vector carrying SFGR in Inner Mongolia. Studying the genetic diversity and population structure of Rickettsia is essential for developing effective control strategies and predicting evolutionary trends of Rickettsia. Methods: In 2019 we collected 408 D. nuttalli in the Inner Mongolia Autonomous Region, detected the percentage of Rickettsia-positive specimens, and characterized the haplotypes. From the Rickettsia-positive ticks, the gltA and ompA genes were extracted, amplified, and sequenced. Results: Ten haplotypes of the gltA gene and 22 haplotypes of the ompA gene were obtained. The phylogenetic analysis showed that the haplotypes G1-G7 and G9 of the gltA gene cluster with Rickettsia raoultii, while G8 and G10 cluster with Rickettsia sibirica. Haplotypes O1-O15, O18 and O20-O22 of the ompA gene cluster with R. raoultii, while O16 and O19 cluster with R. sibirica. The average haplotype diversity was 0.3 for gltA and 0.7 for ompA. The average nucleotide diversity was greater than 0.05. Neutrality tests were nonsignificant for Tajima's D results and Fu's Fs results. The fixation index values (F-ST) showed that the degree of genetic differentiation between most sampled populations was small (F-ST < 0.05), whereas some populations showed a medium (F-ST > 0.05) or large (F-ST > 0.15) degree of differentiation. Analysis of molecular variance (AMOVA) revealed that the variation within populations was greater than that between populations. The mismatch analysis of Rickettsia showed double peaks. Conclusions: We found two Rickettsia spp. (R. raoultii and R. sibirica). The high genetic disparity of Rickettsia allows for easy adaption to different environments. Genetic differentiation between populations is small, and Rickettsia populations do not show a geographically differentiated structure. The high rates of retention and infection of Rickettsia in D. nuttalli together with the animal husbandry exchange in Inner Mongolia gradually led to the harmonization of genetic characteristics of Rickettsia across various regions. Overall, the significant genetic diversity and geographical structure of Rickettsia in D. nuttalli are critical for SFGR control.