TY - JOUR A1 - Drouaud, Jan A1 - Camilleri, Christine A1 - Bourguignon, Pierre-Yves A1 - Canaguier, Aurélie A1 - Bérard, Aurélie A1 - Vezon, Daniel A1 - Giancola, Sandra A1 - Brunel, Dominique A1 - Colot, Vincent A1 - Prum, Bernard A1 - Quesneville, Hadi A1 - Mézard, Christine T1 - Variation in crossing-over rates across chromosome 4 of Arabidopsis thaliana reveals the presence of meiotic recombination “hot spots” Y1 - 2006/01/01 JF - Genome Research JO - Genome Research SP - 106 EP - 114 DO - 10.1101/gr.4319006 VL - 16 IS - 1 UR - http://genome.cshlp.org/content/16/1/106.abstract N2 - Crossover (CO) is a key process for the accurate segregation of homologous chromosomes during the first meiotic division. In most eukaryotes, meiotic recombination is not homogeneous along the chromosomes, suggesting a tight control of the location of recombination events. We genotyped 71 single nucleotide polymorphisms (SNPs) covering the entire chromosome 4 of Arabidopsis thaliana on 702 F2 plants, representing 1404 meioses and allowing the detection of 1171 COs, to study CO localization in a higher plant. The genetic recombination rates varied along the chromosome from 0 cM/Mb near the centromere to 20 cM/Mb on the short arm next to the NOR region, with a chromosome average of 4.6 cM/Mb. Principal component analysis showed that CO rates negatively correlate with the G+C content (P =3×10-4), in contrast to that reported in other eukaryotes. COs also significantly correlate with the density of single repeats and the CpG ratio, but not with genes, pseudogenes, transposable elements, or dispersed repeats. Chromosome 4 has, on average, 1.6 COs per meiosis, and these COs are subjected to interference. A detailed analysis of several regions having high CO rates revealed “hot spots” of meiotic recombination contained in small fragments of a few kilobases. Both the intensity and the density of these hot spots explain the variation of CO rates along the chromosome. ER -