Development and application of quality control materials for detection of methylated [STHX]Septin9 DNA in plasma / 临床检验杂志

ABSTRACT

Objective@#To develop a kind of quality control material which simulates clinical specimens for detecting plasma methylated Septin9 (mSEPT9) and investigate the performance for mSEPT9 detection in external quality assessment (EQA) of laboratories. @*Methods@#The cultured Hela and Jurkat cells, known to contain methylated and unmethylated Septin9 gene respectively, were cultured. The genomic DNA of the cells was collected and extracted, and detected by mSEPT9 kit. According to the Ct value, the genomic DNA was diluted into different concentrations of quality control materials with negative plasma. The homogeneity and stability of the quality control materials were evaluated. The panels consisted of 5 blindly coded samples were distributed to EQA participants and the results were summarized and evaluated. @*Results@#The purity and concentration of extracted genomic DNA met with the needs of use and could be used as quality control products for mSEPT9 detection. The homogeneity and stability met with the requirements of China National Accreditation Service for Conformity Assessment. Some of the participating laboratories occurred false positive results and false negative results, and a good linear correlation for the detected results (Ct values) was only observed in about 55.6% of the laboratories. Among the 9 participating laboratories, 7 laboratories (77.8%) performed well, 1 laboratory (11.1%) qualified, and 1 laboratory (11.1%) unqualified. @*Conclusion@#The quality control materials for mSEPT9 detection was successfully developed and the application in external quality assessment should be of great significance for evaluating and improving the detection ability of clinical laboratory.