Shiroishi T, Sagai T, Natsuume-Sakai S, Moriwaki K
Proc Natl Acad Sci U S A. 1987 May;84(9):2819-23. doi: 10.1073/pnas.84.9.2819.
A recombinant H-2 haplotype, designated aw18, was produced that underwent meiotic recombination in the E alpha (I-E alpha chain)--Slp (sex-limited protein) interval of the H-2 class III region between B10.A (H-2a) and wild-derived B10.MOL-SGR (H-2wm7) strains. It appeared that the H-2aw18 haplotype has a single, recessive, lethal mutation, since homozygotes for H-2aw18 were not detected in progeny generated from the intercross of mice that were heterozygous for this H-2 haplotype. Nine newly established recombinant H-2 haplotypes, which arose from the heterozygous mice that resulted from a cross between common inbred H-2 haplotypes and the aw18 haplotype, allowed us to map the lethal gene to the class III region of the H-2 complex. Southern blot analysis indicated that the aw18 haplotype has a deletion of the C4 gene and a deletion of one of the steroid 21-hydroxylase genes. This result was confirmed by an immunodiffusion test that demonstrated the absence of production of the C4 protein in mice of haplotype H-2aw18. All data that were obtained supported the hypothesis that the meiotic, presumably unequal, recombination between homologous chromosomes of the H-2a and H-2wm7 haplotypes caused the deletion of the C4 and the 21-hydroxylase genes.
产生了一种名为aw18的重组H-2单倍型，它在B10.A（H-2a）和野生来源的B10.MOL-SGR（H-2wm7）品系之间的H-2Ⅲ类区域的Eα（I-Eα链）-Slp（性限制蛋白）区间发生了减数分裂重组。H-2aw18单倍型似乎有一个单一的隐性致死突变，因为在该H-2单倍型杂合的小鼠杂交产生的后代中未检测到H-2aw18纯合子。从常见近交H-2单倍型与aw18单倍型杂交产生的杂合小鼠中产生了9种新建立的重组H-2单倍型，这使我们能够将致死基因定位到H-2复合体的Ⅲ类区域。Southern印迹分析表明，aw18单倍型存在C4基因缺失和一个类固醇21-羟化酶基因缺失。免疫扩散试验证实了这一结果，该试验表明H-2aw18单倍型的小鼠不产生C4蛋白。获得的所有数据都支持这样的假设，即H-2a和H-2wm7单倍型同源染色体之间的减数分裂重组（可能是不等重组）导致了C4和21-羟化酶基因的缺失。
