Evolutionary Emergence of Genes Through Retrotransposition

Abstract

Variation in the number of genes among species indicates that new genes are continuously generated over evolutionary times. Evidence is accumulating that transposable elements, including retrotransposons (which account for about 90% of all transposable elements inserted in primate genomes), are potent mediators of new gene origination. Retrotransposons have fostered genetic innovation during human and primate evolution through: (i) alteration of structure and/or expression of pre‐existing genes following their insertion, (ii) recruitment (or domestication) of their coding sequence by the host genome and (iii) their ability to mediate gene duplication via ectopic recombination, sequence transduction and gene retrotransposition.

Comparative analysis of intronless genes in teleost fish genomes: Insights into their evolution and molecular function

“…For instance, L1 retrotransposition is believed to be the most common mechanism for generating SEGs in eukaryotic organisms Marine Genomics 4 (2011) 109-119 (Cordaux and Batzer, 2008;Doenecke and Albig, 2005a;Sakharkar et al, 2006b). The term L1 retrotransposition refers to a mRNA from a "parental" gene being reverse transcribed into cDNA by LINE (L1)-derived enzymes and then inserted elsewhere in the genome (Ostertag and Kazazian, 2001).…”

Genome‐wide analysis of European sea bass provides insights into the evolution and functions of single‐exon genes

“…Most studies on the origin of SEGs and evolution suggest that they are the result of the reverse transcription of mRNA from a "parental" gene into cDNA and its insertion elsewhere in the genome (Ostertag & Kazazian, 2001). This process, known as retrotransposition, is mediated by long interspersed nuclear element 1 (LINE 1)-derived enzymes, which encode a reverse transcriptase enzyme that can produce a DNA copy from any RNA molecule in the cell (Cordaux & Batzer, 2008;Doenecke & Albig, 2005;Kaessmann et al, 2009;Sakharkar et al, 2006). There are two possible outcomes concerning the fate of the retro-transcribed DNA copy.…”