Chromosome Research

, Volume 15, Issue 5, pp 633–651 | Cite as

Meiotic silencing and the epigenetics of sex

  • William G. KellyEmail author
  • Rodolfo Aramayo


The sensing of accurate homologous recognition and pairing between discreet chromosomal regions and/or entire chromosomes entering meiosis is an essential step in ensuring correct alignment for recombination. A component of this is the recognition of heterology, which is required to prevent recombination at ectopic sites and between non-homologous chromosomes. It has been observed that a number of diverged organisms add an additional layer to this process: regions or chromosomes without a homologous counterpart are targeted for silencing during meiotic prophase I. This phenomenon was originally described in filamentous fungi, but has since been observed in nematodes and mammals. In this review we will generally group these phenomena under the title of meiotic silencing, and describe what is known about the process in the organisms in which it is observed. We will additionally propose that the functions of meiotic silencing originate in genome defense, and discuss its potential contributions to genome evolution and speciation.

Key words

chromosome homology meiosis meiotic silencing prophase 1 recombination trans-sensing 


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Copyright information

© Springer 2007

Authors and Affiliations

  1. 1.Biology DepartmentEmory UniversityAtlantaUSA
  2. 2.Department of BiologyTexas A&M UniversityCollege StationUSA

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