Ann Lab Med.  2020 Jan;40(1):72-75. 10.3343/alm.2020.40.1.72.

Performance Evaluation of the QXDx BCR-ABL %IS Droplet Digital PCR Assay

• Chung HJ
• Hur M
• Yoon S
• Hwang K
• Lim HS
• Kim H
• Moon HW
• Yun YM

• KMID: 2457497
• DOI: http://doi.org/10.3343/alm.2020.40.1.72

Abstract

Accurate detection of BCR-ABL fusion transcripts at and below molecular response (MR) 4 (0.01% International Scale [IS]) is required for disease monitoring in patients with chronic myeloid leukemia (CML). We evaluated the analytical performance of the QXDx BCR-ABL %IS (Bio-Rad, Hercules, CA, USA) droplet digital PCR (ddPCR) assay, which is the first commercially available ddPCR-based in vitro diagnostics product. In precision analysis, the %CV was 9.3% and 3.0%, with mean values of 0.031% IS and 9.4% IS, respectively. The assay was linear in the first order, ranging from 0.032% IS to 20% IS. The manufacturer-claimed limit of blank, limit of detection, and limit of quantification were verified successfully. There was a very strong correlation between the results of the QXDx BCR-ABL %IS ddPCR assay and the ipsogen BCR-ABL1 Mbcr IS-MMR (Qiagen, Hilden, Germany) real-time quantitative PCR assay (r=0.996). In conclusion, the QXDx BCR-ABL %IS ddPCR assay can provide reliable results for CML patients.

Keyword

BCR-ABL; Droplet digital PCR; Performance; Evaluation; Chronic myeloid leukemia

MeSH Terms

Humans
In Vitro Techniques
Leukemia, Myelogenous, Chronic, BCR-ABL Positive
Limit of Detection
Polymerase Chain Reaction*

Figure

• 

  Fig. 1 Passing-Bablok regression of the correlation between the QXDx BCR-ABL %IS ddPCR assay and the BCR-ABL Mbcr IS-MMR DX RQ-PCR assay (N=20). Regression line with a 95% CI is shown.Abbreviations: ddPCR, droplet digital PCR; RQ-PCR, real-time quantitative PCR; MR, molecular response; CI, confidence interval.

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