Steinmetz M, Stephan D, Fischer Lindahl K
Cell. 1986 Mar 28;44(6):895-904. doi: 10.1016/0092-8674(86)90012-7.
By chromosome walking in the major histocompatibility complex (MHC) of the BALB/c mouse, we have linked the K region to the I region at the molecular level. Forty-nine overlapping cosmid clones define a stretch of about 600 kb of DNA containing 2 class I and 7 class II genes. Eleven independent recombination events were mapped between the K and the I region marker loci by Southern blot analysis of polymorphic restriction sites. Eight of these events involved crossing-over, at an unusually high frequency of 0.6%-1.5% between genes from Mus musculus castaneus and laboratory mouse strains, and they were confined to two small stretches of DNA. We conclude that recombination hotspots are present at these positions in the two M.m. castaneus MHC haplotypes tested. In contrast, several MHC haplotypes of laboratory mice appear to lack those hotspots.
通过在BALB/c小鼠的主要组织相容性复合体（MHC）中进行染色体步移，我们在分子水平上把K区域与I区域连接起来。49个重叠的黏粒克隆确定了一段约600 kb的DNA片段，其中包含2个I类基因和7个II类基因。通过对多态性限制性位点的Southern印迹分析，在K区域和I区域标记位点之间定位了11个独立的重组事件。其中8个事件涉及交换，小家鼠栗色品系与实验室小鼠品系的基因之间交换频率异常高，为0.6%-1.5%，且它们局限于两段小的DNA片段。我们得出结论，在所测试的两种小家鼠栗色品系MHC单倍型的这些位置存在重组热点。相比之下，实验室小鼠的几种MHC单倍型似乎缺乏这些热点。
