---
_id: '873'
abstract:
- lang: eng
text: New genes commonly appear through complete or partial duplications of pre-existing
genes. Duplications of long DNA segments are constantly produced by rare mutations,
may become fixed in a population by selection or random drift, and are subject
to divergent evolution of the paralogous sequences after fixation, although gene
conversion can impede this process. New data shed some light on each of these
processes. Mutations which involve duplications can occur through at least two
different mechanisms, backward strand slippage during DNA replication and unequal
crossing-over. The background rate of duplication of a complete gene in humans
is 10-9-10-10 per generation, although many genes located within hot-spots of
large-scale mutation are duplicated much more often. Many gene duplications affect
fitness strongly, and are responsible, through gene dosage effects, for a number
of genetic diseases. However, high levels of intrapopulation polymorphism caused
by presence or absence of long, gene-containing DNA segments imply that some duplications
are not under strong selection. The polymorphism to fixation ratios appear to
be approximately the same for gene duplications and for presumably selectively
neutral nucleotide substitutions, which, according to the McDonald-Kreitman test,
is consistent with selective neutrality of duplications. However, this pattern
can also be due to negative selection against most of segregating duplications
and positive selection for at least some duplications which become fixed. Patterns
in post-fixation evolution of duplicated genes do not easily reveal the causes
of fixations. Many gene duplications which became fixed recently in a variety
of organisms were positively selected because the increased expression of the
corresponding genes was beneficial. The effects of gene dosage provide a unified
framework for studying all phases of the life history of a gene duplication. Application
of well-known methods of evolutionary genetics to accumulating data on new, polymorphic,
and fixed duplication will enhance our understanding of the role of natural selection
in the evolution by gene duplication.
author:
- first_name: Fyodor
full_name: Fyodor Kondrashov
id: 44FDEF62-F248-11E8-B48F-1D18A9856A87
last_name: Kondrashov
orcid: 0000-0001-8243-4694
- first_name: Alexey
full_name: Kondrashov, Alexey S
last_name: Kondrashov
citation:
ama: Kondrashov F, Kondrashov A. Role of selection in fixation of gene duplications.
Journal of Theoretical Biology. 2006;239(2):141-151. doi:10.1016/j.jtbi.2005.08.033
apa: Kondrashov, F., & Kondrashov, A. (2006). Role of selection in fixation
of gene duplications. Journal of Theoretical Biology. Elsevier. https://doi.org/10.1016/j.jtbi.2005.08.033
chicago: Kondrashov, Fyodor, and Alexey Kondrashov. “Role of Selection in Fixation
of Gene Duplications.” Journal of Theoretical Biology. Elsevier, 2006.
https://doi.org/10.1016/j.jtbi.2005.08.033.
ieee: F. Kondrashov and A. Kondrashov, “Role of selection in fixation of gene duplications,”
Journal of Theoretical Biology, vol. 239, no. 2. Elsevier, pp. 141–151,
2006.
ista: Kondrashov F, Kondrashov A. 2006. Role of selection in fixation of gene duplications.
Journal of Theoretical Biology. 239(2), 141–151.
mla: Kondrashov, Fyodor, and Alexey Kondrashov. “Role of Selection in Fixation of
Gene Duplications.” Journal of Theoretical Biology, vol. 239, no. 2, Elsevier,
2006, pp. 141–51, doi:10.1016/j.jtbi.2005.08.033.
short: F. Kondrashov, A. Kondrashov, Journal of Theoretical Biology 239 (2006) 141–151.
date_created: 2018-12-11T11:48:57Z
date_published: 2006-03-21T00:00:00Z
date_updated: 2021-01-12T08:20:47Z
day: '21'
doi: 10.1016/j.jtbi.2005.08.033
extern: 1
intvolume: ' 239'
issue: '2'
month: '03'
page: 141 - 151
publication: Journal of Theoretical Biology
publication_status: published
publisher: Elsevier
publist_id: '6773'
quality_controlled: 0
status: public
title: Role of selection in fixation of gene duplications
type: journal_article
volume: 239
year: '2006'
...