全面解读 | 融合基因检测：DNA or RNA? PCR or NGS?

相比DNA水平，RNA水平上融合基因表现为前后两个基因外显子之间的衔接，融合点相对固定。这一特征为精准设计探针或引物提供了先天优势。因此，根据融合基因序列特点，在RNA水平上检测融合基因比DNA水平更易实现。

图1 DNA水平和RNA水平基因融合示意图

图2 RNA测序-融合基因分子数示意图

图3 肺腺癌队列

图4 DNAseq和RNAseq的驱动突变

泛癌人群的基因组图谱研究中，发表在国际顶级期刊Nat Biotechnol上的一篇研究对500例不同肿瘤类型的患者样本进行DNAseq和RNAseq^[4]，研究结果提示在泛癌人群中，相比DNAseq，RNAseq可检测出更多融合基因（图5）。

图5 DNAseq和RNAseq检测的融合基因比较

图6 ALK稀有融合患者的生存曲线

Koichi Goto教授在此次2020 WCLC中还进一步比较了艾德PCR-9基因产品、OPA（50genes NGS-panel，ThermoFisher）和OCA 3个产品的检测失败率及报告时间（TAT）等基本参数（图8）。结果显示艾德PCR-9基因产品在检测成功率，尤其在RNA水平上的检测成功率、报告时间及普及度上均显示出了绝对优势。更高的检测成功率意味着将有更多的患者获得靶向药物治疗的机会；而更短的报告周期，免去了患者“焦急”等待检测报告时的“煎熬”，能够快速获得精准治疗。因此，基于艾德PCR-9基因的临床检测，可让更多患者更“从容”地享受当今精准医学发展带来的福利！

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