Methods and probes for detecting the cis-trans mutant configuration of egfr-t790m and egfr-c797s

Abstract

The invention provides a method and a probe for detecting the cis-trans mutant configuration of EGFR-T790M and EGFR-C797S, and relates to the technical field of gene detection. The method comprises respectively using a probe system that selectively inhibits the wild type of T790 and a probe system that selectively inhibits the wild type of C797 to amplify the sample by PCR, then sequence each amplification product, and determine T790 and C797 in the sample according to the sequencing result mutant configuration. The above method can effectively distinguish the cis-trans mutant configuration of T790M and C797S, with very high specificity, and can directly give sample sequence information; at the same time, it also has the advantage of high sensitivity, using sequential biased amplification and non-biased amplification. Two-stage PCR amplification using low-cost Sanger sequencing can detect mutations as low as 0.1%; NGS sequencing can reduce costs by reducing sequencing depth while ensuring high sensitivity.

Description

technical field [0001] The present invention relates to the technical field of gene detection, in particular to a method and a probe for detecting the cis-trans mutation configuration of EGFR-T790M and EGFR-C797S. Background technique [0002] EGFR mutations mainly occur in the first four exons (18-21) of the intracellular tyrosine kinase (TK) region. There are more than 30 mutations in the TK region. Among them, T790M and C797S mutations on exon 20 are the most difficult gene mutation types found in tumor patients. EGFR gene T790M specifically refers to the mutation of the 790th amino acid site of exon 20 of epidermal growth factor receptor (EGFR) from threonine (T) to methionine (G), and the gene level is expressed as c .2369C>T; EGFR gene C797S specifically refers to the mutation of the 797th amino acid position of EGFR exon 20 from cysteine ​​(C) to serine (S), and the gene level is expressed as c.2389T>A or c.2390G >C. When T790M and C797S are mutated at the...

AI Technical Summary

Problems solved by technology

The third-generation EGFR-TKI Tagrisso / Tagrisso (also known as Osimertinib / Osimertinib, AZD9291) is an irreversible selective TKI, a new generation of targeted drugs that can effectively deal with the T790M mutation, and is aimed at overcoming the secondary drug resistance of T790M Here comes hope, but eventually drug resistance

[0008] Under the existing technology, next-generation gene sequencing technology (NGS) is the only high-sensitivity and high-specificity detection method that can directly provide sequence information to clearly distinguish the cis-trans mutation configuration of C797S and T790M, while other PCR technologies , such as ARMS PCR or digital PCR can only infer the mutation configuration indirectly through the fluorescent signal detected by a single point, and cannot provide sequence information, and cannot make an accurate and uncontroversial direct judgment on the configuration

However, although NGS technology has the characteristics of large throughput, high accuracy and rich information, it is difficult to meet the detection needs of all patients due to the time-consuming, complicated experimental equipment and process, and high cost.

Therefore, there is still a lack of a method and product that has high detection sensitivity, short detection cycle, low cost, and can directly obtain T790M and C797S mutation sequence information to accurately determine the cis-trans mutation configuration.

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