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Tightly coiled chromosomal material that stains deeply during interphase and is believed to be genetically inactive.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biology) the condensed part of a chromosome that stains strongly with basic dyes in nondividing cells and has little genetic activity. Compare euchromatin
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌhɛt ər əˈkroʊ mə tɪn)

the dense, highly stainable part of a chromosome.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
The enhancer region generally showed a different enrichment pattern for histone modifications than around the CTCFbs, suggesting that a local region of heterochromatin is formed close to the expanded CTG-repeat, within a euchromatin region.
Between 14 and 76% of the tumor cells stained positive for heterochromatin protein (HP1[gamma]) (Table 1 and Figure 1).
Trimethylated H3K9 (H3K9me3) is a posttranslational modification, and is commonly linked with both facultative and constitutive heterochromatin formation as well as transcriptional repression (6).
C-band results showed that all constitutive heterochromatin was confined to the X chromosome, differing from the pattern observed in Cavia and Galea.
The research findings described in this media release can be found in the 14 October online issue of Cancer Cell, under the title, "Wip1 controls global heterochromatin silencing via ATM/BRCA1-dependent DNA methylation" by Doria Filipponi(1), Julius Muller(1), Alexander Emelyanov(1) and Dmitry V.
Loss of the Suv39h histone methyltransferases impairs mammalian heterochromatin and genome stability.
On the other hand, histone H3K9 methylation is related to gene silencing and heterochromatin formation.
Distribution of C-band heterochromatin in metaphase chromosomes of the silver crap, Hypophthalmichthys molitrix (Gyprinidae, Pisces).
In EMN method, electric field exposure induced an increase in electrophoretic mobility of cell nuclei (EMN index), decreased numbers of heterochromatin granules near the inner membrane of cell nucleus, and induced cell membrane damage; but cell viability was conserved.
In many cases, transgenes are rapidly inactivated (silenced), probably by the influence of the neighboring heterochromatin that makes them inaccessible to transcriptional machinery (24), (25).
Finally, emerging evidence indicates that some mature miRNAs are transported back to the nucleus, where they mediate the formation of heterochromatin (3) (Gonzalez et al.