Griffiths R, Double M C, Orr K, Dawson R J
Molecular Laboratory, DEEB, Glasgow University, UK.
Mol Ecol. 1998 Aug;7(8):1071-5. doi: 10.1046/j.1365-294x.1998.00389.x.
Birds are difficult to sex. Nestlings rarely show sex-linked morphology and we estimate that adult females appear identical to males in over 50% of the world's bird species. This problem can hinder both evolutionary studies and human-assisted breeding of birds. DNA-based sex identification provides a solution. We describe a test based on two conserved CHD (chromo-helicase-DNA-binding) genes that are located on the avian sex chromosomes of all birds, with the possible exception of the ratites (ostriches, etc.; Struthioniformes). The CHD-W gene is located on the W chromosome; therefore it is unique to females. The other gene, CHD-Z, is found on the Z chromosome and therefore occurs in both sexes (female, ZW; male, ZZ). The test employs PCR with a single set of primers. It amplifies homologous sections of both genes and incorporates introns whose lengths usually differ. When examined on a gel there is a single CHD-Z band in males but females have a second, distinctive CHD-W band.
鸟类的性别很难区分。雏鸟很少表现出与性别相关的形态特征，据我们估计，在世界上超过50%的鸟类物种中，成年雌性与雄性看起来一模一样。这个问题可能会阻碍鸟类的进化研究以及人工辅助繁殖。基于DNA的性别鉴定提供了一种解决方案。我们描述了一种基于两个保守的CHD（染色体解旋酶DNA结合）基因的检测方法，这两个基因位于所有鸟类的性染色体上，鸵鸟目（鸵鸟等；鸵鸟目）可能除外。CHD-W基因位于W染色体上，因此它是雌性特有的。另一个基因CHD-Z位于Z染色体上，因此在两性中都存在（雌性，ZW；雄性，ZZ）。该检测使用一组引物进行PCR。它扩增两个基因的同源片段，并包含长度通常不同的内含子。在凝胶上进行检测时，雄性有一条单一的CHD-Z条带，而雌性有第二条独特的CHD-W条带。
