On the origin of B-chromosomes: neo XY systems and X-like supernumeraries in Orthoptera

  title={On the origin of B-chromosomes: neo XY systems and X-like supernumeraries in Orthoptera},
  author={Pablo C{\'e}sar Colombo and M. Isabel Remis},
SUMMARYIn previous diversification mechanisms of B-chromosomes were advanced, and conditions for their origin were summarized (GREEN 1990). In the present work, some examples of B-chromosomes in statu nascendi in grasshoppers with neo XY systems are cited, including two cases described in the present work (Sinipta dalmani and Leptysma sp.). It was earlier proposed that increased tolerance to supernumerary Xs due to dosage compensation could contribute to the common occurrence of X-like B… Expand
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  • MI Remis
  • Biology
  • Genetics Selection Evolution
  • 1989
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