
Navigating the hydroxymethylome: experimental biases and quality control tools for the tandem bisulfite and oxidative bisulfite Illumina microarrays
Author(s) -
Ze Zhang,
Min Kyung Lee,
Laurent Praly,
Karl T. Kelsey,
Brock C. Christensen,
Lucas A. Salas
Publication year - 2022
Publication title -
epigenomics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.265
H-Index - 60
eISSN - 1750-1911
pISSN - 1750-192X
DOI - 10.2217/epi-2021-0490
Subject(s) - bisulfite , dna methylation , bisulfite sequencing , computational biology , dna microarray , biology , dna , genetics , gene , gene expression
Aim: Tandem bisulfite (BS) and oxidative bisulfite (oxBS) conversion on DNA followed by hybridization to Infinium HumanMethylation BeadChips allows nucleotide resolution of 5-hydroxymethylcytosine genome-wide. Here, the authors compared data quality acquired from BS-treated and oxBS-treated samples. Materials & methods: Raw BeadArray data from 417 pairs of samples across 12 independent datasets were included in the study. Probe call rates were compared between paired BS and oxBS treatments controlling for technical variables. Results: oxBS-treated samples had a significantly lower call rate. Among technical variables, DNA-specific extraction kits performed better with higher call rates after oxBS conversion. Conclusion: The authors emphasize the importance of quality control during oxBS conversion to minimize information loss and recommend using a DNA-specific extraction kit for DNA extraction and an oxBSQC package for data preprocessing.