Homologous recombination

Homologous recombination is a type of genetic recombination, a process of physical rearrangement occurring between two strands of DNA. Homologous recombination involves the alignment of similar sequences, a crossover between the aligned DNA strands, and breaking and repair of the DNA to produce an exchange of material between the strands. The process homologous recombination naturally occurs in organisms and is also utilized as a molecular biology technique for introducing genetic changes into organism.

Homologous recombination in organisms
The process of homologous recombination occurs during chromosomal crossover, a process occurring during meiosis in eukaryotic organisms that results in a shuffling of genetic material. Homologous recombination is also involved in DNA repair, as organisms repair a damaged region using the material from a partner chromosome as a template. In bacteria, homologous recombination introduces DNA into a bacterium through conjugation, transduction, or natural transformation.

Artificial homologous recombination
Many methods for introducing DNA sequences into organisms to create recombinant DNA and genetically modified organisms use the process of homologous recombination. Also called "gene targeting", the method is especially common in yeast and mouse genetics.