Microsatellite measures of inbreeding: A meta-analysis
Microsatellite measures of inbreeding: A meta-analysis
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DOI：
10.1111/j.0014-3820.2003.tb00309.x
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发表时间：
2003-05-01
期刊：
影响因子：
3.3
通讯作者：
Slate, J
中科院分区：
文献类型：
--
作者：
Coltman, DW;Slate, J
对表型变异与微卫星基因座遗传变异的两个指标多位点杂合性（MLH）和平均d（2）之间已发表和未发表的相关性进行的荟萃分析显示，这些关联的强度通常较弱（平均r < 0.10）。对生活史性状变异的影响在所有报告的效应量上都显著大于零（MLH和平均d（2）的相关系数分别为0.0856和0.0479），而对形态性状的影响则不明显。（r = 0.0052和r = 0.0038），这与生活史性状比形态性状表现出更大的近交衰退的预测相一致。使用平均d（2）报告的效应量比使用MLH报告的效应量更小，更易变，这表明MLH可能是大多数情况下捕获近交衰退的更好指标。然而，使用来自相同数据的两种测量方法报告的配对效应量分析没有显著差异。有几条证据表明，公布的效应大小是向上偏置的。首先，已发表研究的效应量显著高于未发表研究的效应量。第二，报告的效应量的故障安全数字通常相当低，除了MLH和生活史特征之间的相关性。最后，效应量对样本量的回归斜率对于大多数性状都是负的。综上所述，这些结果表明，研究设计检测近亲繁殖抑郁症的生活史性状，使用微卫星将需要超过600人的样本检测平均效应大小（r = 0.10）与合理的统计功率（0.80）。很少有已发表的研究使用接近该值的样本量。
Meta-analyses of published and unpublished correlations between phenotypic variation and two measures of genetic variation at microsatellite loci, multilocus heterozygosity (MLH) and mean d(2), revealed that the strength of these associations are generally weak (mean r < 0.10). Effects on life-history trait variation were significantly greater than zero for both measures over all reported effect sizes (r = 0.0856 and 0.0479 for MLH and mean d(2), respectively), whereas effects on morphometric traits were not (r = 0.0052 and r = 0.0038), which is consistent with the prediction that life-history traits exhibit greater inbreeding depression than morphometric traits. Effect sizes reported using mean d(2) were smaller and more variable than those reported using MLH, suggesting that MLH may be a better metric for capturing inbreeding depression most of the time. However, analyses of paired effect sizes reported using both measures from the same data did not differ significantly. Several lines of evidence suggest that published effects sizes are upwardly biased. First, effect sizes from published studies were significantly higher than those reported in unpublished studies. Second, fail-safe numbers for reported effect sizes were generally quite low, with the exception of correlations between MLH and life-history traits. Finally, the slope of the regression of effect size on sample size was negative for most sets of traits. Taken together, these results suggest that studies designed to detect inbreeding depression on a life-history trait using microsatellites will need to sample in excess of 600 individuals to detect an average effect size (r = 0.10) with reasonable statistical power (0.80). Very few published studies have used samples sizes approaching this value.