Demographic and genetic estimates of effective population size (Ne) reveals genetic compensation in steelhead trout
Demographic and genetic estimates of effective population size (Ne) reveals genetic compensation in steelhead trout
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DOI：
10.1046/j.1365-294x.2003.01705.x
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发表时间：
2003-01-01
影响因子：
4.9
通讯作者：
Kapuscinski, AR
中科院分区：
文献类型：
--
作者：
Ardren, WR;Kapuscinski, AR
为了预测遗传漂变和近亲繁殖对种群进化动力学的影响，需要估计有效种群大小（N-e）。在自然脊椎动物种群中，N-e与性成熟成虫数量（N）的比值如何变化尚未得到解决。我们研究了敏感性N-E/N的波动N和确定的主要变量负责改变的比例在一段时间内的17年的人口的虹鳟鱼（Oncorhynchus mykiss）从华盛顿州。采用人口学和遗传学方法估计N-e。利用8个微卫星位点的数据，通过时间和连锁不平衡方法获得了N-e的遗传估计。从存档的二龄鲑鳞片中扩增用于遗传分析的DNA。1977年至1994年的N-e/N，使用时间方法估计为0.73，同一时期的N-e/N综合人口估计为0.53。人口统计学估计的N-E表明，在生殖成功的变化有最实质性的影响，减少Ne在这个人口中，其次是人口规模的波动。我们发现在低氮时N-e/N比值增加，我们认为这是遗传补偿。结合人口统计学和遗传学方法估计N-e的信息，使我们能够确定繁殖成功方差的减少必须对这种补偿效应负责。了解自然群体的遗传补偿将是有价值的预测N的变化（即高人口密度和瓶颈期）的健身和自然群体的遗传变异的影响。
Estimates of effective population size (N-e) are required to predict the impacts of genetic drift and inbreeding on the evolutionary dynamics of populations. How the ratio of N-e to the number of sexually mature adults (N) varies in natural vertebrate populations has not been addressed. We examined the sensitivity of N-e/N to fluctuations of N and determined the major variables responsible for changing the ratio over a period of 17 years in a population of steelhead trout (Oncorhynchus mykiss) from Washington State. Demographic and genetic methods were used to estimate N-e. Genetic estimates of N-e were gained via temporal and linkage disequilibrium methods using data from eight microsatellite loci. DNA for genetic analysis was amplified from archived smolt scales. The N-e/N from 1977 to 1994, estimated using the temporal method, was 0.73 and the comprehensive demographic estimate of N-e/N over the same time period was 0.53. Demographic estimates of N-e indicated that variance in reproductive success had the most substantial impact on reducing Ne in this population, followed by fluctuations in population size. We found increased N-e/N ratios at low N, which we identified as genetic compensation. Combining the information from the demographic and genetic methods of estimating N-e allowed us to determine that a reduction in variance in reproductive success must be responsible for this compensation effect. Understanding genetic compensation in natural populations will be valuable for predicting the effects of changes in N (i.e. periods of high population density and bottlenecks) on the fitness and genetic variation of natural populations.