---
_id: '3623'
abstract:
- lang: eng
text: 'We present the theoretical background to a new method for measuring genetic
variation for total fitness in Drosophila. The method allows heterozygous effects
on total fitness of whole wild-type chromosomes to be measured under normal demography
with overlapping generations. The wild-type chromosomes are competed against two
balancer chromosomes (B1, B2, say), providing a standard genotype B1/B2 against
which variation in the fitness effects of the wild-type chromosomes can be assessed.
Fitness can be assessed in two ways: (i) at equilibrium of all three chromosomes
under heterozygote advantage, and (ii) during displacement of one balancer by
the other. Equilibrium with all three chromosomes present will be achieved only
if the wild-type homozygote is not too fit, and if the fitnesses of the three
heterozygotes are not too unequal. These conditions were not satisfied for any
of a sample of 12 lethal-bearing chromosomes isolated from a random-bred laboratory
population of Drosophila. At equilibrium, genotypic frequencies show low sensitivity
to changes in genotypic fitness. Furthermore, where all four genotypes are viable
and fertile, supplementary information from cages with only two chromosomes present
and from direct measurements of pre-adult viability are required to estimate fitnesses
from frequencies. The invasion method has the advantages of a greater sensitivity
and of not requiring further data to estimate fitnesses if the wild-type homozygote
is fertile. However, it requires that multiple samples be taken as the invasion
progresses. In a discrete generation model, generation time influences fitness
estimates from this method and is difficult to estimate accurately from the data.
A full age-structured model can also be applied to the data from both types of
experiment. For the invasion method, this gives fitness estimates close to those
from the discrete generation model.'
acknowledgement: This work was supported by grant GR31/G09821 from the BBSRC, and
by fellowships from the Darwin Trust of Edinburgh and the NERC. We are grateful
to the referees for their helpful comments on the manuscript.
article_processing_charge: No
article_type: original
author:
- first_name: Nicholas H
full_name: Barton, Nicholas H
id: 4880FE40-F248-11E8-B48F-1D18A9856A87
last_name: Barton
orcid: 0000-0002-8548-5240
- first_name: Linda
full_name: Patridge, Linda
last_name: Patridge
citation:
ama: Barton NH, Patridge L. Measuring fitness by means of balancer chromosomes.
Genetical Research. 2000;75(3):297-314. doi:10.1017/S0016672399004346
apa: Barton, N. H., & Patridge, L. (2000). Measuring fitness by means of balancer
chromosomes. Genetical Research. Cambridge University Press. https://doi.org/10.1017/S0016672399004346
chicago: Barton, Nicholas H, and Linda Patridge. “Measuring Fitness by Means of
Balancer Chromosomes.” Genetical Research. Cambridge University Press,
2000. https://doi.org/10.1017/S0016672399004346.
ieee: N. H. Barton and L. Patridge, “Measuring fitness by means of balancer chromosomes,”
Genetical Research, vol. 75, no. 3. Cambridge University Press, pp. 297–314,
2000.
ista: Barton NH, Patridge L. 2000. Measuring fitness by means of balancer chromosomes.
Genetical Research. 75(3), 297–314.
mla: Barton, Nicholas H., and Linda Patridge. “Measuring Fitness by Means of Balancer
Chromosomes.” Genetical Research, vol. 75, no. 3, Cambridge University
Press, 2000, pp. 297–314, doi:10.1017/S0016672399004346.
short: N.H. Barton, L. Patridge, Genetical Research 75 (2000) 297–314.
date_created: 2018-12-11T12:04:18Z
date_published: 2000-06-01T00:00:00Z
date_updated: 2023-05-02T12:09:23Z
day: '01'
doi: 10.1017/S0016672399004346
extern: '1'
external_id:
pmid:
- '10893866'
intvolume: ' 75'
issue: '3'
language:
- iso: eng
month: '06'
oa_version: None
page: 297 - 314
pmid: 1
publication: Genetical Research
publication_identifier:
issn:
- 0016-6723
publication_status: published
publisher: Cambridge University Press
publist_id: '2760'
quality_controlled: '1'
scopus_import: '1'
status: public
title: Measuring fitness by means of balancer chromosomes
type: journal_article
user_id: ea97e931-d5af-11eb-85d4-e6957dddbf17
volume: 75
year: '2000'
...