Friedreich's ataxia (GAA)n•(TTC)n repeats strongly stimulate mitotic crossovers in Saccharomyces cerevisae.

Journal Article (Journal Article)

Expansions of trinucleotide GAA•TTC tracts are associated with the human disease Friedreich's ataxia, and long GAA•TTC tracts elevate genome instability in yeast. We show that tracts of (GAA)(230)•(TTC)(230) stimulate mitotic crossovers in yeast about 10,000-fold relative to a "normal" DNA sequence; (GAA)(n)•(TTC)(n) tracts, however, do not significantly elevate meiotic recombination. Most of the mitotic crossovers are associated with a region of non-reciprocal transfer of information (gene conversion). The major class of recombination events stimulated by (GAA)(n)•(TTC)(n) tracts is a tract-associated double-strand break (DSB) that occurs in unreplicated chromosomes, likely in G1 of the cell cycle. These findings indicate that (GAA)(n)•(TTC)(n) tracts can be a potent source of loss of heterozygosity in yeast.

Full Text

Duke Authors

Cited Authors

  • Tang, W; Dominska, M; Greenwell, PW; Harvanek, Z; Lobachev, KS; Kim, H-M; Narayanan, V; Mirkin, SM; Petes, TD

Published Date

  • January 13, 2011

Published In

Volume / Issue

  • 7 / 1

Start / End Page

  • e1001270 -

PubMed ID

  • 21249181

Pubmed Central ID

  • PMC3020933

Electronic International Standard Serial Number (EISSN)

  • 1553-7404

Digital Object Identifier (DOI)

  • 10.1371/journal.pgen.1001270


  • eng

Conference Location

  • United States