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Updated: May 10, 2026

Comprehensive Assessment of Germline Chemical Toxicity Using the Nematode Caenorhabditis elegans
Published on: February 22, 2015
Caenorhabditis elegans compensates for the difference in X chromosome dosage between the sexes by regulating
Abstract:
The primary sex-determining signal in the nematode C. elegans is the ratio of X chromosomes to sets of autosomes (X/A ratio). As a consequence, males (XO; ratio 0.5) and hermaphrodites (XX; ratio 1.0) possess different doses of X-linked genes. Here we demonstrate that C. elegans compensates for this disparity in gene dose by equalizing the levels of X-specific mRNA transcripts in the two sexes. Moreover, we show that mutations in three autosomal genes disrupt the process of dosage compensation. Reduction in the activity of either dpy-21, dpy-27, or dpy-28 results in the overexpression of X-specific genes, 2- to 3-fold above wild-type levels.
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