Genetic differentiation and phylogeny of domestic and wild bovines basedon DNA information

1.我们的研究小组和其他研究人员已经发现，大多数亚洲本地牛起源于与三种不同类型的牛的不同等级的混合物，即无驼背（或欧洲类型）牛，印度zebu牛和banteng（Bos javanicus，东南亚特有的野生牛）。同样，国内的水牛也分为两大类，即沼泽型水牛和河流型水牛。然而，在东亚的一些地区，这两种类型的人口是混合的。原生家牛和水牛具有多基因驯化起源。本研究旨在建立一种利用占亚洲家牛全基因组4%的卫星dna估计遗传构象的有效方法。我们分析了水牛卫星dna的重复序列，发现了两种不同的重复序列。其中一个名为S-I的被BamHI限制性内切酶发现，其重复单元大小为1400bp（使用Stu I限制性内切酶时为800bp和600bp）。另一个重复单元S-II被Bam HI命名为700bp，被Stu i命名为400bp和300bp，通过FISH方法确认S-I和S-II特异定位于染色体的c带区域或着丝粒区域。然而，S-I和S-II染色体上的FISH信号强度不同。水牛S-I和s - ii与牛的同源性分别为79%和81%。因此，如果我们能够选择特定的限制性内切酶，在不同类型的牛或bubaline的卫星dna中产生这些重复单元的特定片段，那么它们的遗传确认将很容易在个体水平上进行估计。我们可以提供必要的信息来建立这种方法。

1.It has been unclosed by our group and other researchers that most Asian native cattle are originated from various grades of mixtures with three distinct types of cattle, that is, the humpless (or European type) cattle, Indian zebu cattle and banteng(Bos javanicus, a wild cattle endemic to Southeast Asia). Similarly, the domestic water buffaloes are classified into two major types, that is, the, swamp type buffaloes and river type buffaloes. In some area of eastern Asia, however there are mixed populations with the two types. The native domestic cattle and water buffaloes have the polygenic origin of domestication.2.The present research aimed to establish an efficient method to estimate genetic conformation of Asian domestic bovines by using satellite DNAs which occupy 4% of the whole genome. We analyzed repeated sequence of satellite DNAs of water buffalo and found two different repeated sequences in the satellite DNAs. One named S-I was found by a restriction enzyme BamHI and 1400bp in size of the repeat-unit (800bp and 600bp when used a restriction enzyme Stu I). The other repeat-unit named S-II was 700bp by Bam HI and 400bp and 300bp by Stu I. The S-I and S-II were confirmed to localize specific to C-band regions or the centromeric regions of the chromosomes by FISH method. However, FISH signal intensity on respective chromosomes were different between S-I and S-II. Homologies of S-I andS-II from the water buffaloes were 79% and 81% to those of cattle, respectively.3.Thus, if we could select specific restriction enzymes to produce specific fragments of those repeat-units in satellite DNAs to different types of bovines or bubalines, their genetic confirmation would be easily estimated at a level of individual. We could give essential information to establish such method.