Advances in tests for colorectal cancer screening and diagnosis.

Tang Q, Cheng J, Cao X, et al., Blood-based DNA methylation as biomarker for breast cancer: a systematic review.

Chandran A, Antony C, Jose L, et al., Mycobacterium Tuberculosis Infection Induces HDAC1-Medicated Suppression of IL-12B Gene Expression in Macrophages.

McCartney D, Stevenson A, Hillary R, et al., Epigenetic signatures of starting and stopping smoking.

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Non-coding RNA may also recruit proteins to modify histones to turn genes “on” or “off.” Non-coding RNA helps control gene expression by attaching to coding RNA, along with certain proteins, to break down the coding RNA so that it cannot be used to make proteins. Your DNA is used as instructions for making coding and non-coding RNA.

When histones are tightly packed together, proteins that ‘read’ the gene cannot access the DNA as easily, so the gene is turned “off.” When histones are loosely packed, more DNA is exposed or not wrapped around a histone and can be accessed by proteins that ‘read’ the gene, so the gene is turned “on.” Chemical groups can be added or removed from histones to make the histones more tightly or loosely packed, turning genes “off” or “on.” Non-coding RNA Typically, methylation turns genes “off” and demethylation turns genes “on.” Histone modificationĭNA wraps around proteins called histones. This chemical group can be removed through a process called demethylation. Typically, this group is added to specific places on the DNA, where it blocks the proteins that attach to DNA to “read” the gene. DNA methylation works by adding a chemical group to DNA.

Khan academy cell biology