Origin and evolution of avian microchromosomes

  title={Origin and evolution of avian microchromosomes},
  author={David W. Burt},
  journal={Cytogenetic and Genome Research},
  pages={97 - 112}
  • D. Burt
  • Published 26 August 2002
  • Biology
  • Cytogenetic and Genome Research
The origin of avian microchromosomes has long been the subject of much speculation and debate. Microchromosomes are a universal characteristic of all avian species and many reptilian karyotypes. The typical avian karyotype contains about 40 pairs of chromosomes and usually 30 pairs of small to tiny microchromosomes. This characteristic karyotype probably evolved 100–250 million years ago. Once the microchromosomes were thought to be a non-essential component of the avian genome. Recent work has… 

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