Yacoub H A, Fathi M M
Department of Biological Sciences, Faculty of Sciences, King Abdul Aziz University , Jeddah , Saudi Arabia.
Mitochondrial DNA. 2013 Oct;24(5):538-51. doi: 10.3109/19401736.2013.770494. Epub 2013 Mar 14.
This study was carried out to figure the potentiality of d-loop of mitochondrial DNA in discriminating among Saudi native chicken strains and other species of genus Gallus. The first 500 base pairs of d-loop region were amplified and successfully sequenced. The results indicated that native chicken strains and genus Gallus species have a tandem repeat sequence with (14) base units into a two copy. Also, there was clear evidence that the native chickens have a unique tandem repeat sequence with (42) base units as a two copy. Two haplotypes (T) and (C) were observed in native chicken strains. Our research displayed approximately (26) transition substitutions in nucleotide sequences specific for native chicken strains, whereas it was 120 mutant sites in case of other species of Gallus. We found that the genetic divergence between these types of chickens was very low (0.022). The phylogenetic tree revealed that each strain of native chicken belonged to each other with the same cluster. In addition, each strain has its own cluster in some individuals. The results showed that the native chicken strains are closely related to Gallus gallus and its subspecies G. g. spadiceus and G/. g. bankiva.
本研究旨在探究线粒体DNA的d-loop在区分沙特本土鸡品种与原鸡属其他物种方面的潜力。扩增了d-loop区域的前500个碱基对并成功测序。结果表明，本土鸡品种和原鸡属物种具有一个由14个碱基单位组成的串联重复序列，呈两个拷贝。此外，有明确证据表明本土鸡具有一个由42个碱基单位组成的独特串联重复序列，为两个拷贝。在本土鸡品种中观察到两种单倍型（T）和（C）。我们的研究显示，本土鸡品种特有的核苷酸序列中大约有26个转换替换，而原鸡属其他物种则有120个突变位点。我们发现这些鸡品种之间的遗传差异非常低（0.022）。系统发育树显示，每个本土鸡品种在同一簇中相互归属。此外，在一些个体中，每个品种都有自己的簇。结果表明，本土鸡品种与原鸡及其亚种红原鸡和原鸡指名亚种密切相关。
