Peltomäki P, Halme A, de la Chapelle A
Department of Medical Genetics, University of Helsinki, Finland.
Genes Chromosomes Cancer. 1989 Sep;1(1):42-7. doi: 10.1002/gcc.2870010108.
Nine males with testicular germ cell tumors were studied by Southern blotting using probes recognizing different regions of the X and Y chromosomes. In the tumors of three patients, an imbalance was noted with a relative deficiency of DNA of Y-chromosomal and a concurrent excess of that of X-chromosomal origin. The X:Y signal ratios were 4, 4, and 2, respectively, in tumor DNA relative to normal DNA, and the ratios of Y to an autosomal locus were 0.4, 0.6, and 0.7, respectively, in the same tumors. Several loci on both arms of the Y chromosome were similarly involved. No structural abnormalities of Y chromosome DNA could be demonstrated. The X/Y change occurred in two of the three patients with nonseminomatous tumors and in two of the three patients with metastatic disease. To account for the results, two alternative models are discussed: first, loss of the Y chromosome and increase in X chromosome number in some but not all tumor cells; second, polyploidization with one Y chromosome and several X chromosomes.
利用识别X和Y染色体不同区域的探针，通过Southern印迹法对9例睾丸生殖细胞肿瘤男性患者进行了研究。在3例患者的肿瘤中，发现存在失衡现象，即Y染色体来源的DNA相对不足，同时X染色体来源的DNA过量。相对于正常DNA，肿瘤DNA中的X:Y信号比分别为4、4和2，在相同肿瘤中，Y与常染色体基因座的比率分别为0.4、0.6和0.7。Y染色体双臂上的几个基因座也有类似情况。未发现Y染色体DNA存在结构异常。X/Y变化发生在3例非精原细胞瘤患者中的2例以及3例转移性疾病患者中的2例。为解释这些结果，讨论了两种替代模型：第一，部分而非全部肿瘤细胞中Y染色体丢失且X染色体数目增加；第二，一个Y染色体和几个X染色体的多倍体化。
