Microgeographic Population Genetic Structure of Baylisascaris procyonis (Nematoda: Ascaroidae) in Western Michigan Indicates the Grand River Is a Barrier to Gene Flow.
Baylisascaris procyonis , the raccoon roundworm, is increasingly being recognized for its zoonotic and public health importance. Fine-scale analyses of the population genetics of this species have been hampered due to a lack of appropriate genetic markers. To this end, we developed 8 novel polymorphic microsatellites for B. procyonis and used these markers to elucidate microgeographic structuring of this parasite in a 500-km(2) study area in western Michigan. Our analyses revealed significant levels of genetic differentiation amongst the 74 worms collected from 10 different raccoons. Critically, Bayesian clustering indicated 2 genetically distinct groups, one on either side of the Grand River which bisects our study area. Estimates of F(ST), and results from AMOVA and isolation by distance, further corroborated a scenario whereby the river is acting as a barrier to gene flow, a rather unexpected finding given the high vagility of raccoons and microgeographic scale of the analysis. It is possible that the Grand River is a major dispersal barrier for B. procyonis because raccoons are most likely to disperse across the river when it is frozen, and worm burden in raccoons approaches zero during the winter.
Christina A
CA
Sarkissian
Sara K
SK
Campbell
Guha
G
Dharmarajan
Joseph
J
Jacquot
L Kristen
LK
Page
Douglas H
DH
Graham
D000818:Animals; D001107:Architectural Accessibility; D017191:Ascaridida Infections / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D001199:Ascaridoidea / Q000145:classification / Q000235:genetics*; D018509:DNA, Helminth / Q000235:genetics / Q000302:isolation & purification; D051456:Gene Flow / Q000502:physiology*; D005828:Genetics, Population; D060005:Genotyping Techniques; D006579:Heterozygote; D008824:Michigan / Q000453:epidemiology; D018895:Microsatellite Repeats; D011821:Raccoons / Q000469:parasitology*; D045483:Rivers
D018509:DNA, Helminth