Stephan D, Sun H, Lindahl K F, Meyer E, Hämmerling G, Hood L, Steinmetz M
J Exp Med. 1986 May 1;163(5):1227-44. doi: 10.1084/jem.163.5.1227.
Chromosome walking has been used to study the organization of the class I genes in the D and Qa regions of the MHC of the BALB/c mouse and in the D region of the AKR mouse. Five and eight class I genes are found in the D and Qa regions of the BALB/c mouse, respectively, while the AKR mouse contains only a single class I D region gene that has been identified by transfection as the Dk gene. Restriction map homologies and crosshybridization experiments suggest that the multiple class I genes in the D region of the BALB/c mouse have been generated by unequal crossing-over involving class I genes from the Qa region. The expanded D region of BALB/c and other H-2d haplotype mouse strains appears to be metastable, since evidence for gene contraction in the Dd region has been found in two mutant strains. Thus the D region and also the Qa region class I genes are in a dynamic state, evolving by gene expansion and contraction.
染色体步移技术已被用于研究BALB/c小鼠MHC的D区和Qa区以及AKR小鼠D区中I类基因的组织情况。在BALB/c小鼠的D区和Qa区分别发现了5个和8个I类基因,而AKR小鼠仅含有一个I类D区基因,该基因已通过转染鉴定为Dk基因。限制性图谱同源性和交叉杂交实验表明,BALB/c小鼠D区中的多个I类基因是由涉及Qa区I类基因的不等交换产生的。BALB/c和其他H-2d单倍型小鼠品系的扩展D区似乎是亚稳定的,因为在两个突变品系中发现了Dd区基因收缩的证据。因此,D区以及Qa区的I类基因处于动态状态,通过基因扩增和收缩而进化。