Polymorphism and divergence at a Drosophila pseudogene locus.
Polymorphism and divergence at a Drosophila pseudogene locus.
复制标题
果蝇假基因座的多态性和分歧。
DOI：
10.1093/genetics/147.1.199
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发表时间：
1997
期刊：
影响因子：
3.3
通讯作者：
Schaeffer,SW
中科院分区：
文献类型：
--
作者：
Pritchard,JK;Schaeffer,SW
The larval cuticle protein(Lcp)cluster inDrosophila melanogastercontains four functional genes and a closely related pseudogene. A 630-bp fragment including the larval cuticle pseudogene locus(Lcpψ)was nucleotide sequenced in 10 strains ofD. melanogasterand a 458-bpLcpψ fragment fromD. simulanswas also sequenced. We used these data to test the hypotheses that the rates of synonymous and nonsynonymous substitution are equal, that the absolute levels of variation are higher than in functional genes, and that intraspecific polymorphism is correlated with interspecific divergence. As predicted, synonymous and nonsynonymous substitution rates were equivalent, and overall nucleotide divergence betweenD. melanogasterandD. simulans(Jukes-Cantor distance = 0.149 ± 0.150) was extremely high. However, within-species DNA sequence comparisons atLcpψ revealed lower levels of polymorphismthan at many functional loci inD. melanogaster. Using the Hudson, Kreitman, and Aguade(HKA) test, we show that the level of polymorphism inLcpψ withinD. melanogasteris lower than expected given the amount of divergence betweenD. melanogasterandD. simulanswhen the pseudogene data are compared to theAdh5′ flanking region. Because theLcpψ lies in a region of relatively infrequent recombination, we suggest that the low level of within-species polymorphism is the result of background selection.
