Molecular genetic ecology of the diversity in sika deer populations.

1.对象：为了研究日本西卡鹿地方种群的遗传多样性，并探讨生境片断化对遗传分化的影响，我们通过DNA分析测量了种群间和种群内的遗传变异水平。利用遗传数据分析了居群间的遗传分化水平和各居群的遗传多样性水平.研究方法：我们在日本的十个地方收集了西卡的DNA样本：三个来自北海道、岩手、金刚山、兵库、山口、岛根、对马和长崎。利用GeneScan DNA片段分析技术检测了8个微卫星位点的遗传变异.结果和讨论：多重比较检验表明，除长崎外，金山群体的平均观察杂合度（Ho）与其他群体无显著差异，长崎群体的平均观察杂合度显著低于金山、兵库、岛根、对马和山口群体（p<0.01）。我们还发现， ...更多信息 各群体中Ho与平均期望杂合度（He）之间差异不显著。因此，我们的结论是，在小群体的杂合性不一定减少，在较大的群体相比。杂合性的降低不能简单地用岛屿效应或目前的种群规模来解释。我们发现相当大的遗传变异在金刚山人口。数值模拟研究表明，在种群规模不变的情况下，金刚山种群的杂合度在20代内迅速下降。然而，实际的遗传多样性大于模拟的预期。这表明，一个群体内的基因流动将抵消一个孤立群体中遗传漂变的影响。Fst分析表明，尽管北方和南方群体间mtDNA单倍型群没有明显的分离，但地方群体间的遗传分化明显。因此，本研究所用的微卫星标记是分析西卡群体结构的有力工具。少

1. Object : To study current genetic diversity of local populations of Japanese sika deer, and to investigate the effect of habitat fragmentation over genetic differentiation, we measured the level of genetic variations among and within populations by DNA analyses. Genetic data were used to assess the level of genetic differentiation among populations and the level of genetic diversity in each population.2. Methods : We collected DNA samples of sika deer at ten localities in Japan : three from Hokkaido, Iwate, Kinkazan, Hyogo, Yamaguchi, Shimane, Tsushima, and Nagasaki. Genetic variations at eight microsatellite loci were detected by GeneScan DNA fragment analysis.3. Results and Discussion : Multiple comparison test revealed that average observed heterozygosity (Ho) in Kinkazan population did not differ from the others except Nagasaki ; Ho in Nagasaki population was significantly (p<0.01) lower than those in Kinkazan, Hyogo, Shimane, Tsushima, and Yamaguchi populations. We also found n … More o significant difference between Ho and average expected heterozygosity (He) in each population. We, therefore, concluded that heterozygosity in small population is not necessarily reduced in comparison with larger populations. The reduction in heterozygosity can not be explained simply by the island effect nor current population size. We detected considerable genetic variations in Kinkazan population. Compulter simulation study demonstrated that heterozygosity in Kinkazan population will decrease rapidly within 20 generation if the population size is constant. However, actual genetic diversity is greater than what expected from the simulation. This suggests that a gene flow within a population would conter the effect of genetic drift in an isolated population. Fst analysis showed that the genetic differentiation among local populations is evident although there are no clear separation between northern and southern mtDNA haplotype groups. The microsatellite markers tested in our study were, therefore, proved to be powerful tools in dissecting population structure of sika deer. Less