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Comparative analysis of diagnostic platforms for measurement of differentially methylated insulin DNA.

ABSTRACT: Circulating cell-free DNA (cfDNA) has been intensively investigated as a diagnostic and prognostic marker for various cancers. In recent years, presence of unmethylated insulin cfDNA in the circulation has been correlated with pancreatic ?-cell death and risk of developing type 1 diabetes. Digital (d)PCR is an increasingly popular method of quantifying insulin cfDNA due to its ability to determine absolute copy numbers, and its increased sensitivity when compared to the more routinely used quantitative PCR. Multiple platforms have been developed to carry out dPCR. However, not all technologies perform comparably, thereby necessitating evaluation of each platform. Here, we compare two dPCR platforms: the QuantStudio 3D (QS3D, Applied Biosystems) and the QX200 (Bio-Rad), to measure copies of unmethylated/methylated insulin plasmids. The QS3D detected greater copy numbers of the plasmids than the QX200 (manual mode), whereas QX200 demonstrated minimal replicate variability, increased throughput, ease of use and the potential for automation. Overall, the performance of QX200, in our hands, was better suited to measure differentially methylated insulin cfDNA.

SUBMITTER: Farr RJ

PROVIDER: S-EPMC6641562 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Comparative analysis of diagnostic platforms for measurement of differentially methylated insulin DNA.

Farr Ryan J RJ Wong Wilson K M WKM Maynard Cody-Lee CL Tersey Sarah A SA Mirmira Raghavendra G RG Hardikar Anandwardhan A AA Joglekar Mugdha V MV

Journal of biological methods 20190603 2

Circulating cell-free DNA (cfDNA) has been intensively investigated as a diagnostic and prognostic marker for various cancers. In recent years, presence of unmethylated insulin cfDNA in the circulation has been correlated with pancreatic β-cell death and risk of developing type 1 diabetes. Digital (d)PCR is an increasingly popular method of quantifying insulin cfDNA due to its ability to determine absolute copy numbers, and its increased sensitivity when compared to the more routinely used quant ...[more]

PMID: 31328130

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Dataset Information

Comparative analysis of diagnostic platforms for measurement of differentially methylated insulin DNA.

Publications

Comparative analysis of diagnostic platforms for measurement of differentially methylated insulin DNA.

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