混合系白血病基因重排的检测方法及其临床意义

为了研究混合系白血病（MLL）基因重排在急性白血病（AL）中的发生率、融合基因类型及其临床意义，用荧光原位杂交技术检测60例急性白血病（AL）患者MLL基因重排，对于MLL基因重排阳性的患者，用巢式RT—PCR方法检测MLL基因重排形成的6种常见融合基因类型。结果表明：7例AL患者有MLL基因重排，发生率为11．67％，其中2例为急性髓细胞白血病M5（AML—M5），融合基因均为MLL／AF9；男5例为B细胞系急性淋巴细胞白血病（B—ALL），其中2例融合基因为MLL／ENL，1例MLL／AF4，2例未扩增出融合基因产物。结论：荧光原位杂交技术是检测ALMLL基因易位重排的快速、特异、灵敏的方法，巢式RT-PCR是检测MLL基因重排产生的融合基因类型的简便可行的方法；MLL基因重排的检测对急性白血病预后判断和治疗方案的选择具有重要意义。

Detection of Rearrangements of Mixed Lineage Leukemia Gene and Its Clinical Significance

To study the incidence, the types of fusion genes and the clinical significance of rearrangements of mixed lineage leukemia (MLL) gene in acute leukemia (AL), the rearrangements of MLL gene of 60 patients with AL were detected by fluorescence in situ hybridization (FISH) and 6 types of common fusion genes resulting from the rearrangements of MLL gene were detected by nested RT-PCR. The results showed that 7 out of 60 AL patients were found the rearrangements of MLL gene, the incidence of which was 11.67%. 2 out of 7 patients were diagnosed as AML-M5, 5 patients were diagnosed as B-ALL. The fusion genes of the 2 AML-M5 patients who had the rearrangements of MLL gene were MLL/AF9. Among 5 B-ALL patients, 2 patients were confirmed to express MLL/ENL, 1 patient was confirmed to express MLL/AF4, the other 2 patints did not express the fusion genes. It is concluded that FISH is a fast, specific and sensitive method to detect the rearrangements of MLL gene in AL patients and nested RT-PCR is a convenient and feasible method to detect the types of fusion genes resulting from the rearrangements of MLL gene. The detection of MLL gene rearrangement is of great importance in predicting prognosis and guiding therapy in AL.