Ahmad Firoz, Rajput Saket, Mandava Swarna, Das Bibhu Ranjan
Research and Development Division, Super Religare Laboratories Ltd., Mumbai, India.
Genet Test Mol Biomarkers. 2012 Jul;16(7):707-15. doi: 10.1089/gtmb.2011.0317. Epub 2012 Jun 25.
Mutation in the CAAT/enhancer binding protein-α (CEBPA) gene has been reported as being one of the common genetic abnormalities in acute myeloid leukemia (AML) and is associated with a good clinical outcome. We intend to explore the prevalence of CEBPA mutations and evaluate the efficacy of fragment and sequencing analysis methods for CEBPA mutation detection in Indian AML patients.
The coding region of the CEBPA gene was screened in 36 normal karyotype AML patients by fragment analysis and direct sequencing.
We identified five CEBPA sequence variations in three patient samples (8.3%) by direct sequencing analysis, of which three were novel mutations. These mutations were clustered mostly in the TAD1 and basic region leucine zipper region of the CEBPA protein. Six cases demonstrated a previously reported polymorphism. Two of the three positive cases showed double mutations, and one case had a single mutation. All five mutations were also detected by fragment analysis, indicating a sensitivity of 100% (5/5). No correlation with clinical parameters including age, sex, white blood cell count, hemoglobin, and platelet count between patients with and without mutation was observed. Interestingly, CEBPA mutations were significantly higher in patients with WT1 mutation, while no correlation with FLT3 and NPM1 was observed.
We report for the first time the frequency of CEBPA mutation from an Indian patients (8.3%). The identification of novel CEBPA mutations added new insights into the genetic heterogeneity of AML. Our result suggests that the optimal approach for detecting CEBPA mutations in AML can be a combination of fragment analysis and direct sequencing.
据报道,CCAAT/增强子结合蛋白α(CEBPA)基因突变是急性髓系白血病(AML)常见的基因异常之一,且与良好的临床预后相关。我们旨在探究印度AML患者中CEBPA基因突变的发生率,并评估片段分析和测序分析方法检测CEBPA基因突变的效能。
采用片段分析和直接测序法,对36例核型正常的AML患者的CEBPA基因编码区进行筛查。
通过直接测序分析,我们在三个患者样本(8.3%)中鉴定出五个CEBPA序列变异,其中三个为新突变。这些突变大多聚集在CEBPA蛋白的TAD1和碱性区域亮氨酸拉链区域。六例显示为先前报道的多态性。三个阳性病例中有两个显示双重突变,一个病例有单一突变。片段分析也检测到了所有五个突变,表明灵敏度为100%(5/5)。未观察到有突变和无突变患者之间与年龄、性别、白细胞计数、血红蛋白和血小板计数等临床参数的相关性。有趣的是,WT1基因突变的患者中CEBPA基因突变显著更高,而未观察到与FLT3和NPM1的相关性。
我们首次报道了印度患者中CEBPA基因突变的频率(8.3%)。新CEBPA基因突变的鉴定为AML的基因异质性增添了新见解。我们的结果表明,检测AML中CEBPA基因突变的最佳方法可以是片段分析和直接测序相结合。