Ohresser M, Borsa P, Delsert C
Laboratoire Gńome et populations, UPR CNRS 9060, Génétique des Populations marines, Station Méditerranénne de l'Environnement Littoral, Quai de la Daurade, Sete, France.
Mol Mar Biol Biotechnol. 1997 Jun;6(2):123-30.
A novel intron-length polymorphism at the actin gene locus mac-1 is here reported and used as a genetic marker for population studies in mussels of the genus Mytilus. Two closely related genes subsequently identified as alleles, mac-1a1 and mac-1b1, from a genomic library of M. galloprovincialis were partially cloned and sequenced. They mainly differed from each other by a 65-bp insertion within their first intron. Polymerase chain reaction (PCR) primers were designed outside the insertion. The PCR analysis of 166 individual mussels from M. galloprovincialis and M. edulis populations revealed three size-classes of alleles or allelomorphs, two of which were of the expected sizes for mac1a1 and mac-1b1. One allelomorph was absent from M. edulis samples, although it was present at substantial frequencies in M. galloprovincialis populations. The frequencies of the two other allelomorphs significantly differed between M. galloprovincialis and M. edulis populations. The comparison of six mac-1 intron sequences over 277 bp showed at once that allelomorphs encompassed alleles differing from one another by substantial numbers of mutations, and that identical alleles were present in both M. galloprovincialis and M. edulis individuals, a probable result of the recent introgression between the two species.
本文报道了肌动蛋白基因位点mac - 1处一种新的内含子长度多态性，并将其用作贻贝属群体研究的遗传标记。随后从加利福尼亚贻贝的基因组文库中部分克隆并测序了两个密切相关的基因，鉴定为等位基因mac - 1a1和mac - 1b1。它们的主要区别在于第一个内含子中有一个65个碱基对的插入。在插入片段之外设计了聚合酶链反应（PCR）引物。对来自加利福尼亚贻贝和紫贻贝群体的166个个体贻贝进行PCR分析，发现了三种大小类别的等位基因或对偶基因，其中两种的大小与mac1a1和mac - 1b1预期大小相符。一种对偶基因在紫贻贝样本中不存在，尽管它在加利福尼亚贻贝群体中以相当高的频率出现。加利福尼亚贻贝和紫贻贝群体中另外两种对偶基因的频率存在显著差异。对277个碱基对的六个mac - 1内含子序列进行比较，立刻发现对偶基因包含彼此有大量突变差异的等位基因，并且相同的等位基因同时存在于加利福尼亚贻贝和紫贻贝个体中，这可能是这两个物种近期基因渗入的结果。
