Mathematical glimpse on the Y chromosome degeneration

  • M. P. Lobo
Statistical Physics and Biological Information


The Y chromosomes are genetically degenerate and do not recombine with their matching partners X. Non-recombination of XY pairs has been pointed out as the key factor for the degeneration of the Y chromosome. The aim here is to show that there is a mathematical asymmetry in sex chromosomes which leads to the degeneration of Y chromosomes even in the absence of XX and XY recombination. A model for sex-chromosome evolution in a stationary regime is proposed. The consequences of their asymmetry are analyzed and lead us to a couple of conclusions. First, Y chromosome degeneration shows up \(\sqrt{2}\) more often than X chromosome degeneration. Second, if nature prohibits female mortalities from beeing exactly \(50\%\), then Y chromosome degeneration is inevitable.


87.23.Cc Population dynamics and ecological pattern formation 87.23.Kg Dynamics of evolution 


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Copyright information

© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2006

Authors and Affiliations

  1. 1.Instituto de Física Teórica, Universidade Estadual PaulistaSão PauloBrazil

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