摘要
为探讨兔痒螨是否会受兔品种、温度带和地域来源的不同而出现遗传变异,采用PCR技术首次对我国6个省份共68个獭兔来源(陕西、河北、河南和湖北)和肉兔来源(山东和四川)痒螨虫株的线粒体细胞色素氧化酶b(cytb)基因全序列进行扩增,经测序后分析遗传变异情况。68条兔痒螨cytb全序列均为1 100bp,共有96个(8.7%)变异位点和46个单倍型;我国整体种群的单倍型多样性(Hd)和核苷酸多样性(π)分别为0.959 2和0.012 0,具有较高的遗传多样性;我国兔痒螨整体种群的中性检验结果为负值(Tajima’s D=-0.444 01,Fu’s Fs=-1.454 25),且呈现多峰的错配分布曲线现象,暗示我国兔痒螨可能经历过突增长过程;我国所有种群间存在一定的遗传分化(Fst=0.262 2)、基因流水平较低(Nm=0.7);分子方差(AMOVA)分析表明遗传分化主要发生在种群内;单倍型网络图和NJ树显示我国兔痒螨的聚类与兔品种、温度带和地理来源无关。结果表明,我国6个地区的兔痒螨虫株呈现较高的遗传多样性,具有一定的遗传分化,但未形成以兔品种、温度带和地理分布为格局的遗传结构。
In order to investigate whether the genetic variation in Psoroptes cuniculi be affected by species of rabbit, temperature zone and geographical origin, the complete sequence of mitochon- drial cytochrome b （cytb） gene of 68 P. cuniculi samples from 6 different provinces, including isolates from rex-rabbit （Shaanxi, Hebei, Henan and Hubei） and meat-type rabbit （Shandong and Sichuan）, were amplified and sequenced for the first time. Then, we analyzed the genetic variability of those P. cuniculi isolates, inferred by cytb sequences. The full length of cytb gene from 68 P. cuniculi isolates were all 1 100 bp. These sequences contained 96 variable sites and 46 haplotypes. The values of haplotypes diversity （Hd= 0. 959 2） and nucleotide diversity （π= 0. 012 0） in overall China population indicated a high genetic diversity. The negative value of neu- trality tests （Tajima＇s D =0.444 01,Fu＇s Fs=-1.454 25）and the phenomenon of mismatch distribution curve with multiple peak suggested that P. cuniculi population in China occurred ex- pansion event in the past. There was a certain genetic differentiation （Fst=0. 262 2） and low gene flow （Nm=0.7） between different geographic populations. An analysis of molecular vari-ance （AMOVA） showed that the genetic differentiation mainly occurred within the population. Haplotype network and NJ phylogenetie tree were both showed that P. cuniculi isolates from China did not cluster according to the species of rabbit, temperature zone and geographical origin. The results indicated that P. cuniculi population from 6 different provinces of China had a high level of genetic diversity and a certain genetic differentiation, however, the genetic structure based on the species of rabbit, temperature zone and geographical origin has not found.
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2017年第4期714-721,共8页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
国家自然科学基金青年基金项目(31402188)
四川农业大学学科"双支计划"(03570422)
