title: Evidence for Inbreeding and Genetic Differentiation among Geographic Populations of the Saprophytic Mushroom Trogia venenata from Southwestern China.
abstract: During the past 40 years, more than 400 Sudden Unexplained Deaths (SUDs) have occurred in Yunnan, southwestern China. Epidemiological and toxicological analyses suggested that a newly discovered mushroom called Trogia venenata was the leading culprit for SUDs. At present, relatively little is known about the genetics and natural history of this mushroom. In this study, we analyzed the sequence variation at four DNA fragments among 232 fruiting bodies of T. venenata collected from seven locations. Our ITS sequence analyses confirmed that all the isolates belonged to the same species. The widespread presence of sequence heterozygosity within many strains at each of three protein-coding genes suggested that the fruiting bodies were diploid, dikaryotic or heterokaryotic. Within individual geographic populations, we found significant deviations of genotype frequencies from Hardy-Weinberg expectations, with the overall observed heterozygosity lower than that expected under random mating, consistent with prevalent inbreeding within local populations. The geographic populations were overall genetically differentiated. Interestingly, while a positive correlation was found between population genetic distance and geographic distance, there was little correlation between genetic distance and barium concentration difference for the geographic populations. Our results suggest frequent inbreeding, geographic structuring, and limited gene flow among geographic populations of T. venenata from southwestern China.
authors.affiliation: Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China.|Institute of Communicable Disease Control and Prevention, Guizhou Provincial Centre for Disease Control and Prevention, Guiyang, Guizhou, PR China.
authors.forename: Fei
authors.initials: F
authors.lastname: Mi
authors.affiliation: Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China.
authors.forename: Dan
authors.initials: D
authors.lastname: Yang
authors.affiliation: Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China.
authors.forename: Xiaozhao
authors.initials: X
authors.lastname: Tang
authors.affiliation: Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China.
authors.forename: Pengfei
authors.initials: P
authors.lastname: Wang
authors.affiliation: Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China.
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: He
authors.affiliation: Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China.
authors.forename: Yunrun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China.
authors.forename: Jianyong
authors.initials: J
authors.lastname: Dong
authors.affiliation: Yunnan Institute for Tropical Crop Research, Jinghong, Yunnan, PR China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Kunming Edible Fungi Institute of All China Federation of Supply and Marketing Cooperatives, Kunming, Yunnan, PR China.
authors.forename: Chunli
authors.initials: C
authors.lastname: Liu
authors.affiliation: Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China.
authors.forename: Ke-Qin
authors.initials: KQ
authors.lastname: Zhang
authors.affiliation: Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, Yunnan, PR China.|Department of Biology, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Jianping
authors.initials: J
authors.lastname: Xu
mesh_terms: D000363:Agaricales / Q000235:genetics*; D001499:Bayes Theorem; D002681:China; D016000:Cluster Analysis; D021901:DNA, Intergenic / Q000235:genetics; D018628:Gene Dosage; D056426:Genetic Loci; D014644:Genetic Variation; D005843:Geography; D007178:Inbreeding; D015810:Linkage Disequilibrium / Q000235:genetics; D010802:Phylogeny; D012098:Reproduction; D017422:Sequence Analysis, DNA
chemical_list: D021901:DNA, Intergenic