Position-effect variegation after 60 years

Trends Genet. 1990 Dec;6(12):422-6. doi: 10.1016/0168-9525(90)90304-o.


Position-effect variegation in Drosophila--the mosaic expression of a gene placed adjacent to a junction between euchromatin and heterochromatin--remains an enigma. However, new insights are being gained from recent studies of genetic modifiers, new model systems, and variegating genes showing exceptional behavior.

Publication types

  • Review

MeSH terms

  • Animals
  • Chromosomes / ultrastructure
  • Drosophila / genetics*
  • Gene Expression
  • Heterochromatin / ultrastructure*
  • Mosaicism


  • Heterochromatin