Randi E, Gentile L, Boscagli G, Huber D, Roth H U
Istituto Nazionale per la Fauna Selvatica, Ozzano dell'Emilia, BO, Italy.
Heredity (Edinb). 1994 Nov;73 ( Pt 5):480-9. doi: 10.1038/hdy.1994.146.
We used the polymerase chain reaction and nucleotide sequencing to study mitochondrial DNA (mtDNA) genetic variability of brown bears (Ursus arctos) belonging to some western European populations. Demographic decline and isolation have apparently shaped genetic variability within and between populations. Small relict bear populations were apparently monomorphic and fixed for different mtDNA haplotypes. Genetic relationships among mtDNA haplotypes suggested the existence of a phylogeographic structure. We discuss the possible roles of historical and demographic factors in determining the observed genetic patterns. The low genetically effective size of the studied brown bear populations points to risks of continuing future loss of gene diversity and increase in inbreeding. Artificial gene flow through restocking could alleviate inbreeding depression in small isolated brown bear populations, and mtDNA phylogeographic relationships may provide a framework for their genetic management.
我们运用聚合酶链反应和核苷酸测序技术，研究了西欧部分棕熊（ Ursus arctos ）种群的线粒体DNA（mtDNA）遗传变异性。种群数量的下降和隔离显然塑造了种群内部和种群之间的遗传变异性。小型残留熊种群显然是单态的，并固定为不同的mtDNA单倍型。mtDNA单倍型之间的遗传关系表明存在系统地理结构。我们讨论了历史和人口因素在决定观察到的遗传模式中可能发挥的作用。所研究的棕熊种群较低的遗传有效规模表明，未来基因多样性持续丧失和近亲繁殖增加的风险。通过重新引入进行人工基因流动可以缓解小型孤立棕熊种群的近亲繁殖衰退，而mtDNA系统地理关系可能为其遗传管理提供一个框架。
