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

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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.