Description

The Human Methylation Atlas tracks display genome-wide DNA methylation profiles from deep whole-genome bisulfite sequencing (WGBS) of 39 primary human cell types sorted from 205 healthy tissue samples. This comprehensive resource enables fragment-level analysis across thousands of unique markers, providing a detailed reference for cell-type-specific methylation patterns.

The atlas comprises two track sets:

DNA methylation patterns are highly reproducible across individuals of the same cell type (>99.5% identical), reflecting the robustness of cell identity programs. Unsupervised clustering of these methylomes recapitulates key elements of tissue ontogeny and developmental lineage relationships.

Display Conventions and Configuration

Signal Tracks

Signal tracks display methylation beta values on a 0-1 scale, where 0 indicates fully unmethylated CpGs and 1 indicates fully methylated CpGs. A value of -1 indicates missing data. For optimal comparison across cell types, set the vertical viewing range to 0-1 with auto-scale off.

Merged signal tracks aggregate data across biological replicates for each cell type. Individual replicate tracks are available for detailed analysis.

Track Colors

Tracks are colored by tissue/cell type category as follows:

ColorCell Type(s)
 Neurons
 Oligodendrocytes
 Thyroid Epithelium
 Prostate Epithelium
 Bladder Epithelium
 Heart Cardiomyocytes
 Smooth Muscle
 Heart Fibroblasts
 Skeletal Muscle
 Erythrocyte Progenitors
 Blood Granulocytes
 Blood Monocytes/Macrophages
 Blood T Cells
 Blood B Cells
 Blood NK Cells
 Pancreas Beta Cells
 Pancreas Alpha Cells
 Pancreas Delta Cells
 Pancreas Duct Cells
 Pancreas Acinar Cells
 Colon Epithelium
 Colon Fibroblasts
 Small Intestine Epithelium
 Gastric Epithelium
 Gallbladder
 Liver Hepatocytes
 Lung Bronchus Epithelium
 Lung Alveolar Epithelium
 Kidney Epithelium
 Endothelial
 Breast Basal Epithelium
 Breast Luminal Epithelium
 Fallopian Epithelium
 Ovary Epithelium
 Adipocytes
 Epidermal Keratinocytes
 Dermal Fibroblasts
 Bone Osteoblasts
 Head Neck Epithelium

Methods

Sample Collection and Sequencing

Primary human cells were isolated from freshly dissociated adult healthy tissues using fluorescence-activated cell sorting (FACS), yielding high-purity preparations across major cell lineages. A total of 205 samples representing 77 primary cell types were collected from 137 consenting donors and merged into 39 cell type groups based on methylation similarity. Average sample purity exceeded 90% as determined by flow cytometry, gene expression, and DNA methylation analysis.

Whole-genome bisulfite sequencing was performed using 150 bp paired-end reads at an average sequencing depth of 30× (minimum 6.62×). Libraries were prepared using the Accel-NGS Methyl-Seq DNA library preparation kit and sequenced on the Illumina NovaSeq 6000 platform.

Processing and Analysis

Reads were mapped to the human genome (hg38) using bwa-meth, deduplicated with Sambamba, and processed into per-CpG methylation calls. The genome was segmented into 7.1 million non-overlapping methylation blocks using a multi-channel dynamic programming algorithm that identifies regions of homogeneous methylation across samples.

Cell-type-specific differentially methylated regions were identified using a one-versus-all comparison approach. Regions uniquely unmethylated in specific cell types were found to be enriched for transcriptional enhancers and tissue-specific transcription factor binding motifs.

Data processing was performed using wgbstools, an open-source computational suite for DNA methylation sequencing data representation, visualization, and analysis.

Data Access

The raw data for these tracks can be explored interactively using the Table Browser or the Data Integrator. For automated analysis, the data may also be queried from our REST API.

The complete dataset, including all WGBS data files and processed methylation calls, is available from GEO accession GSE186458.

For questions regarding the data, please contact Prof. Tommy Kaplan at the Hebrew University of Jerusalem.

Credits

Data generation and analysis were performed at the Hebrew University of Jerusalem by the Dor, Kaplan, and Glaser laboratories and collaborators. Sample collection involved collaboration with Hadassah Medical Center, Oregon Health & Science University, Karolinska Institute, and University of Alberta.

Track development and UCSC Genome Browser integration by the UCSC Genome Browser Group.

References

Loyfer N, Magenheim J, Peretz A, Cann G, Bredno J, Klochendler A, Fox-Fisher I, Shabi-Porat S, Hecht M, Pelet T et al. A DNA methylation atlas of normal human cell types. Nature. 2023 Jan;613(7943):355-364. PMID: 36599988

Loyfer N, Rosenski J, Kaplan T. wgbstools: a computational suite for DNA methylation sequencing data analysis. Life Sci Alliance. 2026 Apr;9(4):e202503514. PMID: 41611450