Definition
Chromosomal crossover, or crossing over, is the exchange of genetic material during sexual reproduction between two homologous chromosomes' non-sister chromatids that results in recombinant chromosomes. It is one of the final phases of genetic recombination, which occurs in the pachytene stage of prophase I of meiosis during a process called synapsis. Synapsis is usually initiated before the synaptonemal complex develops and is not completed until near the end of prophase I. Crossover usually occurs when matching regions on matching chromosomes break and then reconnect to the other chromosome, resulting in chiasma which are the visible evidence of crossing over.
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AlleleAntigenic shiftAzoospermiaBacterial conjugationBacterial transformationBarbara McClintockBase pairBivalent (genetics)Cell (biology)CentiMorganCentromereChiasma (genetics)Chorthippus brunneusChromatidChromosomal translocationChromosomeChromosome segregationCoefficient of coincidenceComplementary DNACrossing-over valueDNA helicaseDNA polymerase III holoenzymeDNA repairDNA replicationDNA sequenceDeletion (genetics)Directionality (molecular biology)DiseaseDmc1DrosophilaEukaryoteExonucleaseFANCMFrans Alfons JanssensFrequencyFusion geneGameteGeneGene conversionGene duplicationGenealogyGenetic distanceGenetic linkageGenetic mapGenetic markerGenetic recombinationGeneticsGenomeHarriet CreightonHolliday junctionHomologous chromosomeHomologous recombinationHorizontal gene transferIndependent assortmentInsertion (genetics)Ionizing radiationKaryotypeLeptotene stageLigaseLinkage disequilibriumLocus (genetics)MeiosisMeiotic non-disjunctionMelanoplus femurrubrumMendelian inheritanceMismatch repairMitotic crossoverMobile genetic elementsMuller's morphsMutantMutationNucleoproteinProbabilityProkaryoteProphase IProtein Data BankProtein dimerRAD51Rad51Radiation hybrid mappingReassortmentRecombinant frequencyRecombinaseSaccharomyces cerevisiaeSegregation (materials science)Sequence homologySexual reproductionSister chromatid exchangeSister chromatidsSpo11SporeStatistical hypothesis testingSynapsisSynaptonemal complexTemplate strandTetrahedronThomas Hunt MorganTransduction (genetics)TransfectionTransformation (genetics)Transposable elementUnequal crossing overViral shiftVirusX-ray
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