# A method of detecting IDH2 gene mutations in angioimmunoblastic T-cell lymphoma based on droplet digital PCR

## TL;DR

This paper introduces a new method using ddPCR to detect IDH2 gene mutations in AITL patients' cfDNA, offering high sensitivity and accuracy.

## Contribution

A novel ddPCR method for detecting specific IDH2 mutations in AITL with high precision and sensitivity.

## Key findings

- The ddPCR method achieved detection limits as low as 0.2% mutation ratio at 1 ng/µl concentration.
- The method showed 100% agreement with sequencing results in 40 clinical samples.
- Precision measurements across different operators and labs had coefficients of variation under 5%.

## Abstract

探究基于微滴式数字PCR（droplet digital PCR，ddPCR）技术建立血管免疫母细胞性T细胞淋巴瘤（angioimmunoblastic T-cell lymphoma，AITL）循环游离DNA（cell-free DNA，cfDNA）中IDH2基因突变的检测方法，并对该方法进行性能评估。

针对IDH2 p.R172K、IDH2 p.R172M和IDH2 p.R172W突变，设计特异性引物探针，优化不同引物组合，建立ddPCR最佳反应体系并通过来源于南京医科大学第一附属医院40例AITL患者的临床cfDNA样本评估该方法的准确度、精密度、分析特异性及检出限。

通过优化引物组合，选用IDH2 R172K/M/W F2/R2引物组合建立IDH2 R172K/M/W突变的ddPCR检测方法。采用特异性标准品检测未观察到假阳性事件；准确度标准品测量结果相对偏差均在±10％范围内；检出限测试表明，所建立的方法能够检出浓度为1 ng/µl、突变比率为0.2％的IDH2 R172K/M/W突变；不同实验者、轮次、实验室的精密度测量结果变异系数均<5％；对40例IDH2 R172K/M/W突变型的临床样本进行基因检测，结果与基因测序结果完全一致。

ddPCR可检测AITL的cfDNA中IDH2基因的突变状态和丰度，具有操作简便、快速、灵敏度和特异性强的优点，能够实现绝对定量，可应用于AITL的诊断和病情监测。