Balazs I, Purrello M, Rubinstein P, Alhadeff B, Siniscalco M
Proc Natl Acad Sci U S A. 1982 Dec;79(23):7395-9. doi: 10.1073/pnas.79.23.7395.
Using a phage lambda Charon 4A recombinant DNA clone (lambdaCH4A-rHs18) from a human genomic library, Wyman and White detected a multiallelic common polymorphism at an EcoRI site (D14S1) flanking the DNA region homologous to the probe [Wyman, A. R. & White, R. (1980) Proc. Natl. Acad. Sci. USA 77, 6754-6758]. Subsequent studies, carried out with the cell hybrid approach and the use of a subclonal derivative (pAW101) from lambdaCH4A-rHs18 have assigned this locus to autosome 14 between 14q21 and 14qter [De Martinville, B., Wyman, A. R., White, R. & Franke, U. (1982) Am. J. Hum. Gen. 34, 216-226]. The data presented here permit the precise mapping of this locus to the subtelomeric region of autosome 14, below band 14q32, in close proximity to the heavy chain gamma1 immunoglobulin locus. These conclusions are supported by three independent lines of evidence, including studies on gene dosage, somatic cell hybrids, and pedigree analysis. Our results are in agreement with the recent assignment of the heavy chain gamma1 immunoglobulin locus to band 14q32 [Kirsch, I. R., Morton, C. C., Nakahara, K. & Leder, P. (1982) Science 216, 301-303] and are consistent with the generally held contention that one unit of meiotic recombination corresponds approximately to one million base pairs. It is to be expected that the location of the highly polymorphic D14S1 site at a measurable distance from the cluster of the heavy chain genes will provide new opportunities for a genetic approach to the question of the specific gene order within the cluster, its possible individual variation, and its biological significance in normal development and disease. It is worthwhile to point out that such a highly polymorphic DNA sequence is located in the same chromosomal region where so much somatic rearrangement goes on normally (i.e., switch region between classes of heavy chain constant region genes) and which is involved with de novo translocations associated with malignancies.
怀曼和怀特利用来自人类基因组文库的噬菌体λ Charon 4A重组DNA克隆(λCH4A-rHs18),在与探针同源的DNA区域侧翼的一个EcoRI位点(D14S1)检测到一个多等位基因常见多态性[怀曼,A. R. & 怀特,R.(1980年)《美国国家科学院院刊》77,6754 - 6758]。随后,采用细胞杂交方法并使用来自λCH4A-rHs18的亚克隆衍生物(pAW101)进行的研究,已将该基因座定位于常染色体14上14q21和14qter之间[德·马丁维尔,B.,怀曼,A. R.,怀特,R. & 弗兰克,U.(1982年)《美国人类遗传学杂志》34,216 - 226]。此处呈现的数据允许将该基因座精确映射到常染色体14的亚端粒区域,在14q32带以下,紧邻重链γ1免疫球蛋白基因座。这些结论得到三条独立证据线的支持,包括基因剂量研究、体细胞杂种研究和系谱分析。我们的结果与最近将重链γ1免疫球蛋白基因座定位于14q32带的研究结果一致[基尔希,I. R.,莫顿,C. C.中原,K. & 莱德,P.(1982年)《科学》216,301 - 303],并且与普遍持有的观点一致,即一个减数分裂重组单位大约对应一百万个碱基对。可以预期,高度多态性的D14S1位点在距重链基因簇可测量距离处的位置,将为以遗传学方法研究该基因簇内特定基因顺序问题、其可能的个体变异以及其在正常发育和疾病中的生物学意义提供新机会。值得指出的是,这样一个高度多态性的DNA序列位于同一个染色体区域,在该区域通常发生大量体细胞重排(即重链恒定区基因类别之间的转换区),并且该区域与恶性肿瘤相关的新生易位有关。