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Unknown,Transcriptomics,Genomics,Proteomics

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Genome-wide mapping of crossovers in all products of adult, single human female meioses reveals structural rearrangements of chromosomes and meiotic drive for recombinant chromatids

ABSTRACT: Meiotic recombination promotes genomic diversity by generating new combinations of alleles, while at the same time, maintaining genome stability by preventing chromosome missegregation and aneuploidy, such as Down Syndrome. We report here the first genome-wide maps of meiotic recombination in the human female meiosis. By utilizing information from all three meiotic products (oocyte, polar body 1 and polar body 2), our data reveal crossover rates that are in great excess (~40%) of recombination rate estimates from population-based studies. Recovery of all three meiotic products allowed us to identify structural defects to meiotic chromosomes that originate during meiosis, as well as true meiotic drive at meiosis II for the preferential exclusion of non-recombinant chromatids from the oocyte. Finally, we identify a novel chromosome segregation pattern reminiscent of 'inverted meiosis' that leads to chromosomally-balanced oocytes. The three products of meiosis from 13 oocytes and the gDNA from the five donors were analysed (total of 44 samples). Blank (negative) and positive (genomic DNA) control samples were provided for each DNA amplifiction run. No replicates were included as they were not available. No external references were included.

ORGANISM(S): Homo sapiens

SUBMITTER: Senthilkumar Natesan

PROVIDER: E-GEOD-53539 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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