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Genetics Home Reference: your guide to understanding genetic conditions     A service of the U.S. National Library of Medicine®

Chromatin-modifying enzymes gene family

Reviewed February 2013

What are the chromatin-modifying enzymes genes?

Genes in this family provide instructions for making a group of proteins called chromatin-modifying enzymes. As their name suggests, these enzymes modify chromatin, a complex of DNA and proteins located in the nucleus of each cell. Chromatin is made up of DNA molecules wound tightly around proteins called histones. These proteins help organize the DNA and package it into larger thread-like structures called chromosomes. Chromatin-modifying enzymes alter histones by adding or removing certain small molecules. These changes regulate chromatin structure and influence gene transcription, which is the first step in the production of proteins from genes. Histone modification also influences the repair of damaged DNA and the copying (replication) of DNA molecules.

This family includes three types of chromatin-modifying enzymes: K-acetyltransferases or KATs (also known as histone acetyltransferases); K-methyltransferases or KMTs (also known as histone lysine methyltransferases); and K-demethylases or KDMs (also known as histone lysine demethylases). There are many ways to modify histones; the enzymes in this family each add or remove a specific molecule. K-acetyltransferases add small molecules called acetyl groups. K-methyltransferases add molecules called methyl groups, while K-demethylases remove methyl groups.

Because histone modification influences the transcription of many genes, this process is critical for many aspects of health and development. Mutations in genes in the chromatin-modifying enzyme family result in a wide variety of disorders characterized by intellectual disability, birth defects, and other developmental problems. Somatic (non-inherited) mutations in these genes have also been associated with the development of various types of cancer and non-cancerous tumors.

Which genes are included in the chromatin-modifying enzymes gene family?

The HUGO Gene Nomenclature Committee (HGNC) provides an index of gene families ( and their member genes.

Genetics Home Reference summarizes the normal function and health implications of these members of the chromatin-modifying enzymes gene family: CREBBP, EHMT1, EP300, EZH2, KAT6B, KDM6A, KMT2D, NSD1, PHF8, and TAF1.

What conditions are related to genes in the chromatin-modifying enzymes gene family?

Genetics Home Reference includes these conditions related to genes in the chromatin-modifying enzymes gene family:

  • genitopatellar syndrome
  • Kabuki syndrome
  • Kleefstra syndrome
  • Ohdo syndrome, Say-Barber-Biesecker-Young-Simpson variant
  • prostate cancer
  • Rubinstein-Taybi syndrome
  • Sotos syndrome
  • Weaver syndrome
  • X-linked dystonia-parkinsonism
  • X-linked intellectual disability, Siderius type

Where can I find additional information about the chromatin-modifying enzymes gene family?

You may find the following resources about the chromatin-modifying enzymes gene family helpful.

  • Madame Curie Bioscience Database: Chromatin Mechanisms Regulating Gene Expression In Health And Disease (
  • Biochemistry (fifth edition, 2002): Chromatin Structure Is Modulated Through Covalent Modifications of Histone Tails (
  • Epigenomics Help (2010): About Histone Modification (

What glossary definitions help with understanding the chromatin-modifying enzymes gene family?

cancer ; cell ; chromatin ; disability ; DNA ; domain ; enhancer ; enzyme ; epigenetic ; epigenomic ; gene ; gene transcription ; histone ; inherited ; lysine ; methyl ; methyltransferase ; molecule ; nucleus ; protein ; receptor ; subunit ; transcription

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.


These sources were used to develop the Genetics Home Reference summary for the chromatin-modifying enzymes gene family.

  • Allis CD, Berger SL, Cote J, Dent S, Jenuwien T, Kouzarides T, Pillus L, Reinberg D, Shi Y, Shiekhattar R, Shilatifard A, Workman J, Zhang Y. New nomenclature for chromatin-modifying enzymes. Cell. 2007 Nov 16;131(4):633-6. (
  • Bannister AJ, Kouzarides T. Regulation of chromatin by histone modifications. Cell Res. 2011 Mar;21(3):381-95. doi: 10.1038/cr.2011.22. Epub 2011 Feb 15. Review. (
  • Heightman TD. Chemical biology of lysine demethylases. Curr Chem Genomics. 2011;5(Suppl 1):62-71. doi: 10.2174/1875397301005010062. Epub 2011 Aug 22. (
  • Kouzarides T. Chromatin modifications and their function. Cell. 2007 Feb 23;128(4):693-705. Review. (


The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? ( in the Handbook.

Reviewed: February 2013
Published: February 8, 2016