急性淋巴细胞白血病21号染色体畸变与4和10及17号染色体三倍体相关性的研究

目的：探讨急性淋巴细胞白血病（a-cute lymphoblastic leukemia,ALL）患者21号染色体畸变与4、10、17号染色体三倍体的相关性及其临床意义。方法：在常规细胞遗传学（CC）分析基础上运用荧光原位杂交技术（Fluorescence in Situ Hybridization,FISH）,采用多种DNA探针,对70例ALL患者进行分析。结果：70例ALL患者中有34例出现21号染色体畸变。20例出现了4、10和17号染色体数量上的变化（获得或丢失）。14例、11例和7例分别出现4、10和17号染色体的三倍体。3例患者出现17号染色体丢失但却伴随有21号染色体结构的变化[t（12;21）],1例患者既有4号染色体三体（获得）同时又有17号染色体单体（丢失）。21例出现染色体数目变化（获得）的患者中有18例出现21号染色体数目的变化。15例t（12;21）中有5例出现TEL基因丢失且均无4,10和17号染色体3倍体,相反有1例合并17号染色体丢失。结论：ALL易出现染色体数目非随机的改变,21号染色体结构和数量上的畸变出现明显分离趋势;21号染色体的畸变与4、10和17染色体数量的变化存在相关性,21号染色体结构的畸变较少合并4、10和17号染色体数目的变化。

Association of aberrations of chromosome 21 with trisomies 4, 10 and 17 in patients with acute lymphoblastic leukemia

OBJECTIVE:To investigate the association of aberrations of chromosome 21 with trisomies 4, 10 and 17 in patients with acute lymphoblastic leukemia (ALL) and to determine their clinical significance of those findings. METHODS: A total of 70 patients were included in this study. Both conventional cytogenetics (CC) and fluorescence in situ hybridization (FISH) were carried out. FISH analysis was performed utilizing commercially available DNA probes. RESULTS: Thirty-four out of the 70 patients were found to have chromosome 21 rearrangements. Twenty out of the 70 patients had a gain or loss of chromosomes 4, 10 and 17. Fourteen, eleven and seven patients were found to have trisomies 4, 10 and 17, respectively. Three of the patients had a loss of chromosome 17 and also had t(12;21) and one had a gain of chromosome 4. Eighteen out of the twenty-one patients with chromosome numerical changes had the numerical changes of 21 chromosome. Five out of 15 patients with t(12;21) had a deletion of TEL gene on other homologue of chromosome 12p, among whom none had a gain og chromosome 4, 10 or 17. but one had a loss of chromosome 17. CONCLUSIONS: Nonrandom chromosomal changes are relatively common in patients with ALL. This study clearly demonstrates that numerical and structural changes of chromosome 21 are two different entities; structural changes of chromosome 21 are not associated with the gain or loss of chromosome 4, 10 or 17, there is a relationship between the numerical aberration of chromosome 21 and trisomies 4, 10 and 17 in patients with ALL.