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Updated: Jan 25, 2026

Micromanipulation of Chromosomes in Insect Spermatocytes
Published on: October 22, 2018
Diverse developmental strategies of X chromosome dosage compensation in eutherian mammals
Alexander I Shevchenko1, Elena V Dementyeva, Irina S Zakharova
1Federal Research Centre "Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences", Novosibirsk, Russia. epigene@bionet.nsc.ru.
Abstract:
In eutherian mammals, dosage compensation arose to balance X-linked gene expression between sexes and relatively to autosomal gene expression in the evolution of sex chromosomes. Dosage compensation occurs in early mammalian development and comprises X chromosome upregulation and inactivation that are tightly coordinated epigenetic processes. Despite a uniform principle of dosage compensation, mechanisms of X chromosome inactivation and upregulation demonstrate a significant variability depending on sex, developmental stage, cell type, individual, and mammalian species. The review focuses on relationships between X chromosome inactivation and upregulation in mammalian early development.
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