Hanson I M, Gorman P, Lui V C, Cheah K S, Solomon E, Trowsdale J
Imperial Cancer Research Fund, Lincoln's Inn Fields, London, United Kingdom.
Genomics. 1989 Nov;5(4):925-31. doi: 10.1016/0888-7543(89)90135-3.
Type XI collagen, a minor structural component of cartilage fibrils, is composed of three chains, alpha 1(XI), alpha 2(XI), and alpha 3(XI). Using a cloned fragment of the human alpha 2(XI) collagen gene (COL11A2) as a molecular probe for in situ hybridization and somatic cell hybrid mapping, we have localized the gene to the short arm of chromosome 6, region 21.3. By exploiting the rich source of probes provided by the major histocompatibility complex (MHC) genes, which also map to this chromosomal band, we have constructed macrorestriction maps of the region by pulsed-field gel electrophoresis and have localized the alpha 2(XI) collagen gene to the centromeric extreme of the MHC. Finally, we have demonstrated, by the isolation of overlapping cosmid clones, that the gene is 45 kb centromeric to the HLA-DPB2 locus and oriented with the 3' end toward the MHC. The COL11A2 locus thus demarcates the proximal boundary of the MHC. This finding may have implications for the understanding of certain MHC-linked diseases.
XI型胶原蛋白是软骨纤维的一种次要结构成分，由三条链组成，即α1(XI)、α2(XI)和α3(XI)。我们使用人α2(XI)胶原蛋白基因（COL11A2）的克隆片段作为原位杂交和体细胞杂种定位的分子探针，将该基因定位到6号染色体短臂21.3区域。通过利用主要组织相容性复合体（MHC）基因提供的丰富探针来源（这些基因也定位于此染色体带），我们通过脉冲场凝胶电泳构建了该区域的宏观限制性图谱，并将α2(XI)胶原蛋白基因定位到MHC的着丝粒末端。最后，通过分离重叠的黏粒克隆，我们证明该基因位于HLA-DPB2基因座着丝粒方向45 kb处，并且3'端朝向MHC。因此，COL11A2基因座划定了MHC的近端边界。这一发现可能对理解某些与MHC相关的疾病具有重要意义。
