## Description

DNA methylation is essential for normal development and is associated with silencing large regions of DNA through processes such as imprinting and X-chromosome inactivation. The majority of CpG dinucleotides are methylated in mammals. Unmethylated CpGs occur in segments called "CpG islands", which often lie upstream of genes in the regulatory regions and impact transcription.

## Display Conventions

These tracks are multi-view composite tracks that contains multiple data types (views). Each view within each track has separate display controls, as described here. Most ENCODE tracks contain multiple subtracks, corresponding to multiple experimental conditions. If a track contains a large number of subtracks, only some subtracks will be displayed by default. The user can select which subtracks are displayed via the display controls on the track details pages.

## Credits

These data were generated and analyzed as part of the ENCODE project, a genome-wide consortium project with the aim of cataloging all functional elements in the human genome. This effort includes collecting a variety of data across related experimental conditions, to facilitate integrative analysis. Consequently, additional ENCODE tracks may contain data that is relevant to the data in these tracks.

## References

Illingworth RS, Bird AP. CpG islands--'a rough guide'. FEBS Lett. 2009 Jun 5;583(11):1713-20.

Caiafa P, Zampieri M. DNA methylation and chromatin structure: the puzzling CpG islands. J Cell Biochem. 2005 Feb 1;94(2):257-65.

Latham T, Gilbert N, Ramsahoye B. DNA methylation in mouse embryonic stem cells and development. Cell Tissue Res. 2008 Jan;331(1):31-55.

## Data Release Policy

Data users may freely use ENCODE data, but may not, without prior consent, submit publications that use an unpublished ENCODE dataset until nine months following the release of the dataset. This date is listed in the Restricted Until column on the track configuration page and the download page. The full data release policy for ENCODE is available here.