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Published on: September 7, 2017
Dosage compensation in mammals
Neil Brockdorff1, Bryan M Turner2
1Department of Biochemistry, University of Oxford Oxford OX1 3QU, United Kingdom.
Abstract:
Many organisms show major chromosomal differences between sexes. In mammals, females have two copies of a large, gene-rich chromosome, the X, whereas males have one X and a small, gene-poor Y. The imbalance in expression of several hundred genes is lethal if not dealt with by dosage compensation. The male-female difference is addressed by silencing of genes on one female X early in development. However, both males and females now have only one active X chromosome. This is compensated by twofold up-regulation of genes on the active X. This complex system continues to provide important insights into mechanisms of epigenetic regulation.
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