gene recombination | recombination | genetic recombination | DNA recombination
DEFINITION process by which two DNA molecules exchange genetic information, resulting in the production of a new combination of alleles<sup>1</sup><HR><sup>1</sup> allele [ IATE:1254616 ] REFERENCE Wikipedia. Genetic recombination, http://en.wikipedia.org/wiki/Genetic_recombination [20.1.2014]
COMMENT In viruses, there are two types of recombination, <u>self recombination</u> and <u>recombination with host</u>.<BR><u>Self recombination</u> occurs when two viral genomes recombine by homologous crossing over. This happens for DNA viruses and is very common in prokaryotic viruses, but also for RNA viruses or retroviruses. These recombination events can be of evolutionary advantage for the virus when it helps to evade host immune defenses, for example by changing surface protein antigenicity.<BR><u>Recombination with host or other organism</u> occurs when a viral genome recombine to acquire sequences from another organism. Natural selection can retain acquired sequence if it gives an evolutionary advantage to the virus and mutations can modify its original functions. This event is common in large dsDNA viruses, some eukaryotic viruses even acquired many genes from bacteria.<HR>Reference: <i>Viral genome evolution</i>, http://viralzone.expasy.org/all_by_species/4136.html [11.7.2014]<HR><HR>Not to be confused with:<LI><i>genomic reassortment</i> [ IATE:3561133 ]<LI><i>genomic rearrangement</i> [ IATE:1474160 ].