Convergence and divergence in sex-chromosome evolution
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Updated: Mar 7, 2026

Frequency and Distribution of Crossovers in Caenorhabditis elegans Meiosis by SNP Genotyping using Real-time PCR
Published on: July 11, 2025
1Institute of Ecology and Evolution, University of Bern, Bern, Switzerland.
Abstract:
A sequence assembly of the chicken W chromosome enables reconstruction of the gene content of the W chromosome across 14 bird species and shows striking similarities in the maintenance of broadly expressed and dosage-sensitive genes on highly degenerate sex chromosomes in both birds and mammals. However, the chicken W chromosome is not enriched for genes with expression in female-specific tissues, providing an intriguing contrast to the acquisition and amplification of genes with testis-specific expression on mammalian Y chromosomes and suggesting that the inheritance of chromosomes solely through females or males can lead to different evolutionary outcomes.
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