The crossing over occurs during the prophase 1 of meiosis 1. The exchange of DNA segments between non-sister chromatids during the synapsis is known as the crossing over. The SDSA and DHJ models are described in figure 1. During CO type, both chromosomes are transferred with new genetic information. During NCO type, a repair of the broken strand occurs, only one chromosome, which holds the double-strand break is transferred with the new information. The copying down of information can be either non-crossover (NCO) or crossover (CO) types of the flanking regions. Thus, both SDSA and DHJ pathways are considered as repair mechanisms. Both SDSA and DHJ pathways are initiated by a gap or double-strand break, followed by the invasion of strands to start the copying down of genetic information. The double Holliday junction (DHJ) pathway is another model of copying genetic information, leading to the non-physical transfer of genetic information. This copying of genetic information occurs through synthesis-dependent strand annealing (SDSA), which allows the exchange of information, but not the physical exchange of DNA pieces. On the other hand, sections of genetic material in one chromosome can be copied to another chromosome without exchanging the parts of chromosomes physically. The physical transfer of genetic information occurs through the exchange of chromosome segments between non-sister chromatids. The exchange of genetic information can occur by either physical transfer or non-physical transfer. The homologous chromosome pairing is known as synapsis. The variations of genes in the gametes lead to the production of genetically varied offspring.Įukaryotic genetic recombination occurs through homologous chromosome pairing, followed by the exchange of genetic information between non-sister chromatids. Meiosis is the process of producing gametes for the sexual reproduction. Eukaryotic genetic recombination occurs during prophase 1 of meiosis 1. Genetic recombination is often a natural process. The production of offspring with different combinations of traits compared to their parents is known as recombination in genetics. What is the difference between Recombination and Crossing Over The main difference between recombination and crossing over is that recombination is the production of different combinations of alleles in the offspring whereas crossing over is the exchange of genetic material between non-sister chromatids, the event which produces recombination.ģ. This exchange of DNA segments produces new combinations of alleles among the offspring, which is identified as genetic recombination. Chiasma lets the exchange of DNA segments between non-sister chromatids. Crossing over occurs at points called chiasma, which are created between non-sister chromatids. The pairing of homologous chromosomes during prophase 1 lets the crossing over to occur and crossing over between non-sister chromatids, in turn, lets the recombination to occur.

Both events occur during the prophase 1 of meiosis 1 in eukaryotes. Recombination and crossing over are two correlating processes, which lead to genetic variations among the offspring. Main Difference – Recombination vs Crossing Over

Chiasmata crossover definition