The frequencies of a polymorphic inversion, In(2L)t, and of Adh and αGpdh alleles were analyzed in three natural populations of Drosophila melanogaster from Japan. Significant positive correlations between the frequencies of In(2L)t and AdhS or αGpdhF were detected due to tight linkage. An analysis of correlation with latitude showed that the negative cline of AdhS frequency could be explained entirely by its linkage with In(2L)t; the frequency of AdhS on the standard chromosome did not show a latitudinal cline. To the contrary, the cline of αGpdhF frequency itself was positive, and its linkage with In(2L)t makes the positive cline unclear. These results suggest that the two allozymes themselves respond to latitudinal natural selection in different ways. When these populations were transferred to laboratory cages and maintained for a long time, they lost the chromosomal polymorphism but retained stable enzyme polymorphisms, although allele frequencies in the cage were not the same as in nature. The frequencies of Adh and αGpdh alleles were close to those in earlier cage populations of the same geographical origin.
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机译：在来自日本的果蝇的三个自然种群中，分析了一个多态倒位In（2L）t以及Adh和αGpdh等位基因的频率。由于紧密键合，检测到In（2L）t和Adh S 或αGpdh F 的频率之间存在显着的正相关。与纬度的相关性分析表明，Adh S 频率的负谱线可以完全通过与In（2L）t的联系来解释。标准染色体上Adh S 的频率未显示出纬度cline。相反，αGpdh F 频率的谱线本身是正的，并且它与In（2L）t的联系使得正谱线不清楚。这些结果表明，两种同工酶本身以不同的方式对纬度自然选择产生响应。当这些种群转移到实验室笼中并维持了很长一段时间后，它们失去了染色体多态性，但保持了稳定的酶多态性，尽管笼中的等位基因频率与自然中的频率不同。 Adh和αGpdh等位基因的频率接近于相同地理起源的早期笼子种群。
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