Department of Physiological, Biochemical and Cell Sciences, and Center for Biotechnology Development and Biodiversity Research, University of Sassari, Italy.
Comp Biochem Physiol Part D Genomics Proteomics. 2009 Sep;4(3):168-73. doi: 10.1016/j.cbd.2009.02.002. Epub 2009 Feb 15.
In order to investigate the polymorphism of ?-globin chain of hemoglobin amongst caprines, the linked (I)? and (II)? globin genes of Barbary sheep (Ammotragus lervia), goat (Capra hircus), European mouflon (Ovis aries musimon), and Cyprus mouflon (Ovis aries ophion) were completely sequenced, including the 5? and 3? untranslated regions. European and Cyprus mouflons, which do not show polymorphic ? globin chains, had almost identical ? globin genes, whereas Barbary sheep exhibit two different chains encoded by two nonallelic genes. Four different ? genes were observed and sequenced in goat, validating previous observations of the existence of allelic and nonallelic polymorphism. As in other vertebrates, interchromosomal gene conversion appears to be responsible for such polymorphism. Evaluation of nucleotide sequences at the level of molecular evolution of the (I)?-globin gene family in the caprine taxa suggests a closer relationship between the genus Ammotragus and Capra. Molecular clock estimates suggest sheep-mouflon, goat-aoudad, and ancestor-caprine divergences of 2.8, 5.7, and 7.1 MYBP, respectively.
为了研究羊科动物血红蛋白β-珠蛋白链的多态性，对巴巴里绵羊（Ammotragus lervia）、山羊（Capra hircus）、欧洲盘羊（Ovis aries musimon）和塞浦路斯野绵羊（Ovis aries ophion）的连接（I）和（II）珠蛋白基因的 5'和 3'非翻译区进行了完全测序。不表现出多态性β-珠蛋白链的欧洲和塞浦路斯盘羊具有几乎相同的β-珠蛋白基因，而巴巴里绵羊则由两个非等位基因编码两种不同的链。在山羊中观察到并测序了四个不同的β基因，证实了以前关于等位基因和非等位基因多态性存在的观察结果。与其他脊椎动物一样，染色体间基因转换似乎是导致这种多态性的原因。对羊科动物（I）-珠蛋白基因家族在分子进化水平上的核苷酸序列进行评估表明，Ammotragus 属与 Capra 属之间的关系更为密切。分子钟估计表明，绵羊-盘羊、山羊-大角羊和祖先-羊的分歧时间分别为 2.8、5.7 和 7.1 MYBP。
