diffMONT: predicting methylation-specific PCR biomarkers based on nanopore sequencing data for clinical application.

Area of Science:

• Genomics
• Molecular Diagnostics
• Bioinformatics

Background:

• DNA methylation is a crucial biomarker for clinical diagnostics, particularly in cancer detection.
• Methylation-specific PCR (MSP) is a rapid screening method, but existing differentially methylated region (DMR) prediction tools, often designed for whole-genome bisulfite sequencing (WGBS), yield large, non-specific regions unsuitable for MSP.
• Nanopore sequencing offers direct DNA methylation analysis without prior DNA treatment, presenting an opportunity for improved diagnostic marker identification.

Purpose of the Study:

• To develop a computational tool, diffMONT, that predicts differentially methylated regions specifically tailored for methylation-specific PCR (MSP) primer design.
• To bridge the gap between theoretical cancer marker research and practical clinical applications by enabling the rapid translation of methylation data into diagnostic assays.

Main Methods:

• The diffMONT tool was developed as an open-source Python-based application.
• diffMONT incorporates primer and amplicon lengths, requires one condition to be unmethylated, and considers the minimal differentially methylated cytosines within primer regions.
• Performance was evaluated by comparing diffMONT's predictions with those from metilene and DSS using publicly available nanopore sequencing data.

Main Results:

• diffMONT predicts differentially methylated regions that are more specific towards hypermethylated regions compared to existing tools.
• The tool's predictions are optimized for MSP primer design, facilitating practical diagnostic assay development.
• Comparison with metilene and DSS demonstrated diffMONT's enhanced specificity for MSP applications.

Conclusions:

• diffMONT accelerates the design of methylation-specific diagnostic assays by providing tailored predictions for MSP.
• The tool effectively addresses the limitations of existing DMR prediction methods for PCR-based diagnostics.
• diffMONT facilitates the practical application of DNA methylation analysis in clinical diagnostics and cancer research.