title: Unequal crossing over in the ribosomal DNA of Saccharomyces cerevisiae.
abstract: Unequal sister chromatid exchanges occur at the ribosomal DNA locus of yeast during mitotic growth. The frequency of unequal crossing over, as measured by the deletion or duplication of an inserted genetic marker (LEU2), is sufficient to maintain the sequence homogeneity of the rDNA repeat units.
mesh_terms: D002872:Chromosome Deletion; D003434:Crossing Over, Genetic; D004261:DNA Replication; D004271:DNA, Fungal / Q000235:genetics*; D005796:Genes; D008040:Genetic Linkage; D007930:Leucine / Q000235:genetics; D008938:Mitosis; D010957:Plasmids; D012335:RNA, Ribosomal / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D012854:Sister Chromatid Exchange
chemical_list: D004271:DNA, Fungal; D012335:RNA, Ribosomal; D007930:Leucine