title: Genome-wide survey of post-meiotic segregation during yeast recombination.
abstract: BACKGROUND
  When mismatches in heteroduplex DNA formed during meiotic recombination are left unrepaired, post-meiotic segregation of the two mismatched alleles occurs during the ensuing round of mitosis. This gives rise to somatic mosaicism in multicellular organisms and leads to unexpected allelic combinations among progeny. Despite its implications for inheritance, post-meiotic segregation has been studied at only a few loci.
  
  
  RESULTS
  By genotyping tens of thousands of genetic markers in yeast segregants and their clonal progeny, we analyzed post-meiotic segregation at a genome-wide scale. We show that post-meiotic segregation occurs in close to 10% of recombination events. Although the overall number of markers affected in a single meiosis is small, the rate of post-meiotic segregation is more than five orders of magnitude larger than the base substitution mutation rate. Post-meiotic segregation took place with equal relative frequency in crossovers and non-crossovers, and usually at the edges of gene conversion tracts. Furthermore, post-meiotic segregation tended to occur in markers that are isolated from other heterozygosities and preferentially at polymorphism types that are relatively uncommon in the yeast species.
  
  
  CONCLUSIONS
  Overall, our survey reveals the genome-wide characteristics of post-meiotic segregation. The results show that post-meiotic segregation is widespread in meiotic recombination and could be a significant determinant of allelic inheritance and allele frequencies at the population level.
authors.affiliation: European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
authors.forename: Eugenio
authors.initials: E
authors.lastname: Mancera
authors.forename: Richard
authors.initials: R
authors.lastname: Bourgon
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Huber
authors.forename: Lars M
authors.initials: LM
authors.lastname: Steinmetz
mesh_terms: D002874:Chromosome Mapping; D020090:Chromosome Segregation / Q000235:genetics*; D053903:DNA Breaks, Double-Stranded; D053843:DNA Mismatch Repair / Q000235:genetics; D005787:Gene Frequency; D016681:Genome, Fungal; D055106:Genome-Wide Association Study; D005838:Genotype; D008540:Meiosis / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D011995:Recombination, Genetic / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*