The level and patterns of nucleotide diversity have been characterized for two X-linked loci, fused (fu; a region of 2362 bp) and suppressor of sable (su(s); a region of 413 bp), in one European and one American D. montana population. Sequence variation at these loci shows that the two populations are divergent, although they may not be completely isolated. Data on the level of silent site variability at su(s) (1.1% and 0.5% for the European and American populations, respectively) suggest that the effective population sizes of the two populations may be similar. At the fused locus, one European sequence was highly divergent and may have resulted from gene conversion, and was excluded from the analysis. With this sequence removed, the level of silent site variability was significantly lower in the European population (0.28%) than in the American population (2.3%), which suggests a selective sweep at or near fu in the former population.

中文翻译：

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美国和欧洲果蝇蒙大拿种群的变异水平、种群规模和结构

核苷酸多样性的水平和模式已表征为两个 X 连锁基因座，融合（fu；2362 bp 的区域）和黑貂抑制基因（su(s)；413 bp 的区域），在一个欧洲和一个美洲D. 蒙大拿州人口。这些位点的序列变异表明这两个种群是不同的，尽管它们可能不是完全隔离的。关于 su(s) 的沉默位点变异水平的数据（欧洲和美国种群分别为 1.1% 和 0.5%）表明两个种群的有效种群大小可能相似。在融合基因座上，一个欧洲序列高度分化，可能是由基因转换引起的，因此被排除在分析之外。移除该序列后，欧洲人群的沉默位点变异水平显着降低（0.