What is the main effect of bisulfite conversion in methylation analysis?

Bisulfite conversion is a critical step in methylation analysis, particularly when assessing DNA methylation patterns. The primary effect of bisulfite conversion is to specifically alter cytosine residues by converting them to uracil. This chemical reaction happens when bisulfite is applied to DNA; unmethylated cytosines are converted into uracils, while methylated cytosines remain unchanged.

This distinction allows researchers to identify where methylation is present in the DNA strand. Subsequent amplification and sequencing of the converted DNA enable comparison of the original sequence to the converted sequence, revealing which cytosines were methylated. This process is foundational for understanding gene regulation and epigenetic modifications. The unique conversion pattern ultimately provides insights into various biological processes and disease states associated with aberrant methylation.