title: Genetic diversity and population genetic structure analysis of Echinococcus granulosus sensu stricto complex based on mitochondrial DNA signature.
abstract: The genetic diversity and population genetics of the Echinococcus granulosus sensu stricto complex were investigated based on sequencing of mitochondrial DNA (mtDNA). Total 81 isolates of hydatid cyst collected from ungulate animals from different geographical areas of North India were identified by sequencing of cytochrome c oxidase subunit1 (coxi) gene. Three genotypes belonging to E. granulosus sensu stricto complex were identified (G1, G2 and G3 genotypes). Further the nucleotide sequences (retrieved from GenBank) for the coxi gene from seven populations of E. granulosus sensu stricto complex covering 6 continents, were compared with sequences of isolates analysed in this study. Molecular diversity indices represent overall high mitochondrial DNA diversity for these populations, but low nucleotide diversity between haplotypes. The neutrality tests were used to analyze signatures of historical demographic events. The Tajima's D test and Fu's FS test showed negative value, indicating deviations from neutrality and both suggested recent population expansion for the populations. Pairwise fixation index was significant for pairwise comparison of different populations (except between South America and East Asia, Middle East and Europe, South America and Europe, Africa and Australia), indicating genetic differentiation among populations. Based on the findings of the present study and those from earlier studies, we hypothesize that demographic expansion occurred in E. granulosus after the introduction of founder haplotype particular by anthropogenic movements.
authors.affiliation: Department of Parasitology, Post Graduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: Monika
authors.initials: M
authors.lastname: Sharma
authors.affiliation: Department of Microbiology, Sher-i Kashmir Institute of Medical Sciences, Srinagar, Kashmir, Jammu and Kashmir, India.
authors.forename: Bashir Ahmad
authors.initials: BA
authors.lastname: Fomda
authors.affiliation: Department of Community Medicine, Indira Gandhi Medical College, Shimla, Himachal Pradesh, India.
authors.forename: Saligram
authors.initials: S
authors.lastname: Mazta
authors.affiliation: Department of Parasitology, Post Graduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: Rakesh
authors.initials: R
authors.lastname: Sehgal
authors.affiliation: School of Public Health and Zoonoses, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, Punjab, India.
authors.forename: Balbir Bagicha
authors.initials: BB
authors.lastname: Singh
authors.affiliation: Department of Parasitology, Post Graduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: Nancy
authors.initials: N
authors.lastname: Malla
mesh_terms: D000818:Animals; D002020:Buffaloes; D002417:Cattle; D018509:DNA, Helminth / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D048209:Echinococcus granulosus / Q000235:genetics*; D014644:Genetic Variation; D005828:Genetics, Population; D006041:Goats; D006239:Haplotypes; D007194:India; D012756:Sheep
chemical_list: D018509:DNA, Helminth; D004272:DNA, Mitochondrial