Laboratory of Animal Biotechnology, School of Veterinary Medicine, Azabu University, Chūō, Sagamihara, Japan.
Anim Sci J. 2011 Feb;82(1):52-6. doi: 10.1111/j.1740-0929.2010.00819.x. Epub 2010 Oct 4.
The mithun (Bos frontalis), synonymous with mithan and gayal, is considered to be a domesticated form of gaur (B. gaurus). However, there has been a controversy concerning its origin. In an effort to address this issue, the mitochondrial cytochrome b (cytb) genes of 20 mithun from Myanmar and 13 from Bhutan were sequenced to trace its maternal origin. Seven cytb haplotypes were found in the 33 mithun, and the phylogenetic tree for these haplotypes clearly showed three embranchments involving five gaur types, a B. indicus type, and a B. taurus type. Sixteen Myanmar and 12 Bhutan mithun had gaur haplotypes, while a B. indicus haplotype was found in three Myanmar and one Bhutan mithun. The B. taurus haplotype was detected in a single Myanmar animal. These results demonstrated that the principal maternal origin of mithun was gaur and suggested that it was directly domesticated from gaur. However, some introgression of domestic cattle existed in current mithun populations. The presence of cattle mtDNA raised the question of how many cattle nuclear genes might have been integrated into the gene pool of mithun.
野黄牛（Bos frontalis），又称大额牛和野牛，被认为是白肢野牛（B. gaurus）的驯化形式。然而，其起源一直存在争议。为了解决这个问题，我们对来自缅甸的 20 头野黄牛和来自不丹的 13 头野黄牛的线粒体细胞色素 b（cytb）基因进行了测序，以追溯其母系起源。在这 33 头野黄牛中发现了 7 种 cytb 单倍型，这些单倍型的系统发育树清楚地显示了三个分支，涉及 5 种白肢野牛类型、一种印度野牛类型和一种黄牛类型。16 头缅甸野黄牛和 12 头不丹野黄牛具有白肢野牛单倍型，而 3 头缅甸野黄牛和 1 头不丹野黄牛具有印度野牛单倍型。一头缅甸野黄牛具有黄牛单倍型。这些结果表明，野黄牛的主要母系起源是白肢野牛，表明它是直接从白肢野牛驯化而来的。然而，目前野黄牛群体中存在一些家牛的基因渗入。牛的 mtDNA 的存在提出了一个问题，即有多少牛的核基因可能已经整合到野黄牛的基因库中。
