Schmoll Tim, Janzon Volker, Epplen Jörg T, Lubjuhn Thomas
Institute for Evolutionary Biology and Ecology, University of Bonn, An der Immenburg 1, D-53121 Bonn, Germany.
Electrophoresis. 2003 Aug;24(16):2758-63. doi: 10.1002/elps.200305571.
Molecular analyses of genetic parentage in wild bird populations demonstrate that extra-pair paternity (EPP) is common, even in socially monogamous species. After having identified extra-pair offspring (EPO), an important step is to uncover the identity of extra-pair sires (EPS). Studies relying on multilocus DNA fingerprinting face the problem that simple between-gel comparisons of fingerprint banding patterns are imprecise in assigning parentage across gels. To tackle this problem, we developed a method to identify EPS by means of standardized across-gel comparisons of multilocus DNA fingerprints and applied it in a socially monogamous bird species with high levels of EPP, the coal tit (Parus ater). Scanned DNA fingerprint gels and standard image-editing software allowed to screen and reliably identify EPS. Overall, EPP was successfully assigned to 32 different EPS for 143 out of 210 (68.1%) EPO detected. This corresponds well to extra-pair parentage assignment rates revealed by microsatellite-based studies in congeneric species. Our approach proves especially useful whenever multilocus DNA fingerprints for parentage exclusion exist while microsatellite markers are not available.
对野生鸟类种群进行遗传亲子关系的分子分析表明，即使在实行社会单配制的物种中，婚外父权（EPP）也很常见。在确定了婚外子代（EPO）后，重要的一步是找出婚外父本（EPS）的身份。依赖多位点DNA指纹图谱的研究面临这样一个问题，即指纹条带模式在凝胶间的简单比较在跨凝胶确定亲子关系时并不精确。为了解决这个问题，我们开发了一种通过对多位点DNA指纹图谱进行标准化的跨凝胶比较来识别EPS的方法，并将其应用于一种具有高婚外父权水平的社会单配制鸟类——煤山雀（Parus ater）。扫描的DNA指纹凝胶和标准图像编辑软件能够筛选并可靠地识别EPS。总体而言，在检测到的210个EPO中，有143个（68.1%）的EPP成功被确定为32个不同的EPS。这与基于微卫星的同属物种研究揭示的婚外亲子关系确定率非常吻合。我们的方法在存在用于排除亲子关系的多位点DNA指纹图谱而微卫星标记不可用时特别有用。
