---
_id: '3641'
abstract:
- lang: eng
text: The probability of fixation of a mutation with selective advantage s will
be reduced by substitutions at other loci. The effect of a single substitution,
with selective advantage S0016672300032857inline1, can be approximated as a sudden
reduction in the frequency of the favourable allele, by a fraction w = 1 −(s/S)r/s
(where r is the recombination rate). An expression for the effect of a given sequence
of such catastrophes is derived. This also applies to the ecological prxoblem
of finding the probability that a small population will survive, despite occasional
disasters. It is shown that if substitutions occur at a rate Δ, and are scattered
randomly over a genetic map of length R, then an allele is unlikely to be fixed
if its advantage is less than a critical value, Scrit = (π2/6)(2ΔS/(Rlog(S/s))).
This threshold depends primarily on the variance in fitness per unit map length
dueto substitutions, var(W)/R = 2ΔS/R. With no recombination, the fixation probability
can be calculated for a finite population. If Δ > s, it is of the same order
as for a neutral allele ( ≈ Δ/(2N(Δ−s))), whilst if S0016672300032857inline2,
fixation probability is much higher than for a neutral allele, but much lower
than in the absence of hitch-hiking S0016672300032857inline3. These results suggest
that hitch-hiking may substantially impede the accumulation of weakly favoured
adaptations.
author:
- first_name: Nicholas H
full_name: Nicholas Barton
id: 4880FE40-F248-11E8-B48F-1D18A9856A87
last_name: Barton
orcid: 0000-0002-8548-5240
citation:
ama: Barton NH. The reduction in fixation probability caused by substitutions at
linked loci. *Genetical Research*. 1994;64(3):199-208. doi:10.1017/S0016672300032857
apa: Barton, N. H. (1994). The reduction in fixation probability caused by substitutions
at linked loci. *Genetical Research*. Cambridge University Press. https://doi.org/10.1017/S0016672300032857
chicago: Barton, Nicholas H. “The Reduction in Fixation Probability Caused by Substitutions
at Linked Loci.” *Genetical Research*. Cambridge University Press, 1994.
https://doi.org/10.1017/S0016672300032857
.
ieee: N. H. Barton, “The reduction in fixation probability caused by substitutions
at linked loci,” *Genetical Research*, vol. 64, no. 3. Cambridge University
Press, pp. 199–208, 1994.
ista: Barton NH. 1994. The reduction in fixation probability caused by substitutions
at linked loci. Genetical Research. 64(3), 199–208.
mla: Barton, Nicholas H. “The Reduction in Fixation Probability Caused by Substitutions
at Linked Loci.” *Genetical Research*, vol. 64, no. 3, Cambridge University
Press, 1994, pp. 199–208, doi:10.1017/S0016672300032857 .
short: N.H. Barton, Genetical Research 64 (1994) 199–208.
date_created: 2018-12-11T12:04:23Z
date_published: 1994-12-01T00:00:00Z
date_updated: 2021-01-12T07:44:51Z
day: '01'
doi: '10.1017/S0016672300032857 '
extern: 1
intvolume: ' 64'
issue: '3'
month: '12'
page: 199 - 208
publication: Genetical Research
publication_status: published
publisher: Cambridge University Press
publist_id: '2742'
quality_controlled: 0
status: public
title: The reduction in fixation probability caused by substitutions at linked loci
type: journal_article
volume: 64
year: '1994'
...