Population differences in levels of linkage disequilibrium in the wild
Population differences in levels of linkage disequilibrium in the wild
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DOI：
10.1111/j.1365-294x.2011.05154.x
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发表时间：
2011-07
影响因子：
4.9
通讯作者：
Meng-Hua Li;Juha Merilä
中科院分区：
文献类型：
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作者：
Meng-Hua Li;Juha Merilä
关于野生动物种群中连锁不平衡水平的信息仍然有限，尤其是关于种群间可能存在的连锁不平衡水平的差异。我们在基因组水平上比较了三个种群的LD水平和程度，其中两个种群(Kuusamo和YlläS)代表了物种主要分布区内的近交种群，而第三个种群(Suupohja)是物种分布区边缘的半隔离、部分近亲繁殖的种群。虽然在所有三个种群中都观察到了广泛的远距离LD(>；20 cm)，但LD通常在1-5 cm或约200-600kb的距离内衰退到本底水平。LD的程度和程度在不同种群之间差异很大，但与观察到的种群内遗传变异水平和基于种群历史的预期密切一致。与两个近交系群体相比，群体亚结构最强的自交系群体(Suupohja)的LD水平最高。此外，与其他两个种群相比，Suupohja种群的LD随着距离的增加而衰减得更慢。这些结果表明，在一个物种内相对较短的地理距离内，LD水平可以有很大的差异，这些结果表明，关联图谱的前景因种群而异。在本例中，Suupohja群体的前景最好，因为最小化的标记基因分型和1-5 cM(约200-600 kb)的最小标记间距将足以进行全基因组扫描以检测QTL。
Information about the levels of linkage disequilibrium (LD) in wild animal populations is still limited, and this is true particularly with respect to possible interpopulation variation in the levels of LD. We compared the levels and extent of LD at the genome‐wide scale in three Siberian jay (Perisoreus infaustus) populations, two of which (Kuusamo and Ylläs) represented outbred populations within the main distribution area of the species, whereas the third (Suupohja) was a semi‐isolated, partially inbred population at the margin of the species’ distribution area. Although extensive long‐range LD (>20 cM) was observed in all three populations, LD generally decayed to background levels at a distance of 1–5 cM or c. 200–600 kb. The degree and extent of LD differed markedly between populations but aligned closely with both observed levels of within‐population genetic variation and expectations based on population history. The levels of LD were highest in the most inbred population with strong population substructure (Suupohja), compared with the two outbred populations. Furthermore, the decay of LD with increasing distance was slower in Suupohja, compared with the other two populations. By demonstrating that levels of LD can vary greatly over relatively short geographical distances within a species, these results suggest that prospects for association mapping differ from population to population. In this example, the prospects are best in the Suupohja population, given that minimized marker genotyping and a minimum marker spacing of 1–5 cM (c. 200–600 kb) would be sufficient for a whole genome scan for detecting QTL.