Department of Applied Biology, Faculty of Textile Sciences, Kyoto Institute of Technology, Kyoto, Japan.
J Hered. 2010 Jan-Feb;101(1):26-32. doi: 10.1093/jhered/esp079.
Seasonal environmental changes have the potential to influence the genetic structure of species with a short generation time, such as Drosophila. We previously found the seasonal change in linkage disequilibrium (LD) between the chemoreceptor (Cr) genes in a local Japanese population (Kyoto [KY]). This could be caused by fluctuation in the population size or selection in temporally heterogeneous environments or both. Here, we analyzed the scale of LD between 51 X-linked polymorphisms (10 Cr and 41 non-Cr gene markers) in the 2 seasonal samples from the KY population and an autumn sample from 106 localities in and around Japan (Ja03au). Many of the non-Cr genes have receptor function but fewer functional connections to each other. The magnitude of LD in Ja03au did not significantly differ from that in the KY autumn sample. The lack of local differentiation was confirmed in an autumn sample from another local Japanese population. On the other hand, the magnitude of LD was significantly larger in spring than in autumn in the 2 independent KY samples. This suggests that reduction in the population size during winter increased the magnitude of LD in spring in the mainland population in Japan. Long-distance LD could be a useful measure for assessing seasonal fluctuation in effective population size.
季节环境变化有可能影响世代时间短的物种的遗传结构，例如果蝇。我们之前发现了在日本当地种群（京都[KY]）中化学感受器（Cr）基因之间的连锁不平衡（LD）随季节变化。这可能是由于种群大小的波动或在时间异质环境中的选择或两者共同作用的结果。在这里，我们分析了来自 KY 种群的 2 个季节性样本和来自日本各地和周围的 106 个地点的秋季样本（Ja03au）之间的 51 个 X 连锁多态性（10 个 Cr 和 41 个非 Cr 基因标记）之间 LD 的规模。许多非 Cr 基因具有受体功能，但彼此之间的功能联系较少。Ja03au 中的 LD 大小与 KY 秋季样本没有显著差异。另一个日本当地种群的秋季样本证实了局部分化的缺失。另一方面，在 KY 的 2 个独立样本中，LD 的大小在春季显著大于秋季。这表明冬季种群数量的减少增加了日本大陆种群春季 LD 的大小。长距离 LD 可以作为评估有效种群大小季节性波动的有用指标。
