Orignal Article QUANTIFICATION AND METHYLATION STATUS OF FREE CIRCULATING DNA BASED BIOMARKER IN DIABETIC PATIENTS FOR THE EARLY DIAGNOSIS OF DIABETES MELLITUS THROUGH LIQUID BIOPSY

Abstract

ABSTRACT

Introduction: The prevalence rate of diabetes mellitus (DM) is becoming higher not only in developing countries but also worldwide. The commonly used tests for the diagnosis of DM lack standardization and sensitivity. DNA based free-circulating biomarkers are gaining attention as promising biomarkers for the diagnosis, prognosis, and progression of the different diseases. In DM, β-cell destruction results in the release of free DNA into the plasma which can be quantified by different approaches. In our study, we have quantified and compared the level of total free circulating DNA and methylation status of preproinsulin (INS) DNA fragments levels in the plasma of diabetic patients and healthy controls.

Material and Methods: Our study included 45 diabetics and 45 age and sex matched control individuals. We used Quantitative real-time PCR as a more reliable tool due to high specificity and sensitivity to determine the circulating copies of demethylated INS. The ROC curve was used to determine the sensitivity and specificity of the assay used for diagnosis purposes.

Results: In the plasma of patients, a relatively higher amount of free circulating DNA was observed as compared to the normal healthy person. ROC curve analysis showed strong discrimination potential of fcDNA concentrations for diabetic patient diagnosis with area under the curve to be 0.794 (95% CI: 0.698-0.889; P < 0.05).

Conclusion: These assays may be used to detect the extent of destruction of β-cell death in DM and can give insights into progression and responses to the treatment used.

Key Words:   Free circulating DNA, Diabetes mellitus, Methylation, Preproinsulin