Cell-free DNA methylome profiling by MBD-seq with ultra-low input

Area of Science:

• Epigenetics
• Molecular Biology
• Cancer Research

Background:

• Cell-free DNA (cfDNA) methylation signatures are sensitive biomarkers for cancer detection, classification, and monitoring.
• Current cfDNA methylation analysis predominantly relies on bisulfite conversion, which has limitations.
• Enrichment-based methods like cfMeDIP-seq show potential but require further optimization.

Purpose of the Study:

• To develop and validate an ultra-low input, enrichment-based cfDNA methylation profiling method.
• To establish a bisulfite-free technology for cfDNA methylation analysis.
• To compare the performance of the new method against existing techniques.

Main Methods:

• Optimization of methyl-CpG binding protein (MBD) capture conditions for ultra-low input cfDNA.
• Utilizing methylated filler DNA to enhance capture efficiency.
• Comparative analysis of cfMBD-seq with standard MBD-seq and cfMeDIP-seq.

Main Results:

• Optimized cfMBD-seq demonstrates high correlation with standard MBD-seq for low input amounts.
• cfMBD-seq yields higher sequencing data quality compared to cfMeDIP-seq, with more reads passing filters and lower duplicate rates.
• cfMBD-seq exhibits superior enrichment of CpG islands over cfMeDIP-seq.

Conclusions:

• Developed a novel, bisulfite-free, ultra-low input cfDNA methylation profiling method (cfMBD-seq).
• cfMBD-seq offers improved data quality and CpG island enrichment compared to cfMeDIP-seq.
• This technology holds significant potential for non-invasive and cost-effective cancer detection and classification.