Transvection in Drosophila

Adv Genet. 2002;46:399-420. doi: 10.1016/s0065-2660(02)46014-2.


Pairing-dependent interallelic complementation was first described for the Ultrabithorax gene of the bithorax-complex in Drosophila by Lewis and cited as an example of a new phenomenon that Lewis called the "trans-vection effect." Several different kinds of pairing-dependent gene expression have been observed in Drosophila, and it is now clear that a variety of different molecular mechanisms probably underlie the changes in gene expression that are observed after disrupting chromosome pairing. Transvection in the bithorax-complex appears to result from the ability of cis-regulatory elements to regulate transcription of the promoter on the homologous chromosome. The same phenomenon appears to be responsible for pairing-dependent interallelic complementation at numerous other genes in Drosophila. Some transvection effects are dependent on the presence of wild-type or specific mutant forms of the protein encoded by the zeste trans-regulatory gene, but other transvection effects are zeste-independent. The ease with which chromosome aberrations can disrupt transvection also varies widely among different genes.

Publication types

  • Review

MeSH terms

  • Alleles
  • Animals
  • Chromosome Pairing
  • DNA-Binding Proteins / genetics
  • Drosophila / genetics*
  • Drosophila Proteins
  • Female
  • Gene Expression
  • Gene Silencing
  • Genes, Insect
  • Genetic Complementation Test
  • Male
  • Models, Genetic
  • Recombination, Genetic
  • Transcription Factors


  • DNA-Binding Proteins
  • Drosophila Proteins
  • Transcription Factors
  • ci protein, Drosophila
  • z protein, Drosophila