The duplication of DNA sequences corresponding to genes.
gene duplication occurs when an error in DNA replication leads to the duplication of a region of DNA containing a functional gene. The duplicated gene is free to mutate and may take on new functions. The two genes that exists after a gene duplication event are termed paralogous genes, or paralogs. Gene duplication may have a major role in evolution
Generally, the production of two copies of a DNA sequence. Specifically, the duplication of an entire gene sequence.
the process by which existing genes are duplicated.
A genetic alteration in which a segment of DNA is repeated, Duplications may appear anywhere, but where the duplicated segment is adjacent to the original one, this is termed a tandem duplication.
Gene duplication is any duplication of a region of DNA that contains a gene; it may occur as an error in homologous recombination, a retrotransposition event, or duplication of an entire chromosome. Zhang, J. (2003). "Evolution by gene duplication: an update."