MLPA技术检测儿童ETV6/RUNX1^+急性淋巴细胞白血病基因拷贝数的变异

Detection of copy number variations in pediatric ETV6/RUNX1-positive acute lymphoblastic leukemia with multiplex ligation-dependent probe amplification

目的应用多重连接探针扩增技术(MLPA)检测在ETV6/RUNX1^+急性淋巴细胞白血病(ALL)患儿中基因拷贝数变异的情况,并与常规经典染色体核型分析及荧光原位杂交技术(FISH)检测进行比较,以评估MLPA技术的应用价值。方法回顾性分析2006年1月至2012年11月95例ETV6/RUNX1+ALL患儿的临床资料,包括临床特征、染色体核型检测结果及FISH检测结果。应用MLPA技术检测95例患儿中多个基因拷贝数变异的情况。结果 95例患儿中,73例(77%)检测到基因拷贝数的改变。每例患儿基因拷贝数变异个数的中位数为1(0~6)个。拷贝数变异率超过10%的基因为EBF1、CDKN2A/2B、PAX5、ETV6、RB1、BTG1。以上经MLPA技术检测到拷贝数变异的基因涉及的染色体片段在染色体核型检测中常检测不到改变。FISH技术检测ETV6基因拷贝数的结果与MLPA检测结果的符合率为66%。结论 MLPA可作为高效、简便的方法检测ETV6/RUNX1^+ALL患儿基因拷贝数的变异。

Objective To investigate the application of multiplex ligation-dependent probe amplification（MLPA） in the detection of copy number variations（CNVs） in pediatric ETV6/RUNX1-positive acute lymphoblastic leukemia（ALL）, to compare this method with conventional karyotype analysis and fluorescence in situ hybridization（FISH）, and to evaluate the value of MLPA. Methods The clinical data of 95 children with ETV6/RUNX1-positive ALL who were treated from January 2006 to November 2012 were analyzed retrospectively, including clinical features, results of karyotype analysis, and results of FISH. CNVs were detected with MLPA. Results CNVs were detected in 73（77%）, and the median number of CNVs was 1（range 0-6）. The CNVs of EBF1, CDKN2A/2B, PAX5, ETV6, RB1, and BTG1 were detected in more than 10% of all the patients. The changes in the chromosome segments carrying the genes with CNVs detected by MLPA were not detected by conventional karyotype analysis. The coincidence rate between the CNVs in ETV6 gene detected by FISH and those detected by MLPA was 66%. Conclusions MLPA is an efficient and convenient method to detect CNVs in children with ETV6/RUNX1-positive ALL.