Mannen Hideyuki, Yonesaka Riku, Noda Aoi, Shimogiri Takeshi, Oshima Ichiro, Katahira Kiyomi, Kanemaki Misao, Kunieda Tetsuo, Inayoshi Yousuke, Mukai Fumio, Sasazaki Shinji
Laboratory of Animal Breeding and Genetics, Graduate School of Agricultural Science, Kobe University, Kobe, Japan.
Faculty of Agriculture, Kagoshima University, Kagoshima, Japan.
Anim Sci J. 2017 May;88(5):739-744. doi: 10.1111/asj.12716. Epub 2016 Sep 28.
This study aims to estimate the mitochondrial genetic diversity and structure of Japanese Polled and Kuchinoshima feral cattle, which are maintained in small populations. We determined the mitochondrial DMA (mtDNA) displacement loop (D-loop) sequences for both cattle populations and analyzed these in conjunction with previously published data from Northeast Asian cattle populations. Our findings showed that Japanese native cattle have a predominant, Asian-specific mtDNA haplogroup T4 with high frequencies (0.43-0.81). This excluded Kuchinoshima cattle (32 animals), which had only one mtDNA haplotype belonging to the haplogroup T3. Japanese Polled showed relatively lower mtDNA diversity in the average sequence divergence (0.0020) than other Wagyu breeds (0.0036-0.0047). Japanese Polled have been maintained in a limited area of Yamaguchi, and the population size is now less than 200. Therefore, low mtDNA diversity in the Japanese Polled could be explained by the decreasing population size in the last three decades. We found low mtDNA diversity in both Japanese Polled and Kuchinoshima cattle. The genetic information obtained in this study will be useful for maintaining these populations and for understanding the origin of Japanese native cattle.
本研究旨在评估日本无角牛和口之岛野生牛的线粒体遗传多样性及结构，这两个群体数量较少。我们测定了这两个牛群的线粒体DNA（mtDNA）位移环（D-loop）序列，并结合先前发表的东北亚牛群数据进行分析。我们的研究结果表明，日本本土牛有一个占主导地位的、亚洲特有的mtDNA单倍群T4，频率较高（0.43 - 0.81）。这排除了口之岛牛（32头），它们只有一个属于单倍群T3的mtDNA单倍型。日本无角牛在平均序列差异（0.0020）方面显示出相对较低的mtDNA多样性，低于其他和牛品种（0.0036 - 0.0047）。日本无角牛一直饲养在山口县的有限区域内，目前种群数量不足200头。因此，日本无角牛mtDNA多样性低可以用过去三十年种群数量的减少来解释。我们发现日本无角牛和口之岛牛的mtDNA多样性都很低。本研究获得的遗传信息将有助于维持这些种群，并有助于了解日本本土牛的起源。
