Heterozygosity, inbreeding and neonatal traits in Soay sheep on St Kilda

Andrew Overall, K.A. Byrne, J.G. Pilkington, J.M. Pemberton

Research output: Contribution to journalArticleResearchpeer-review

Abstract

We investigated whether birth weight and neonatal survival, a period within which 24% of all mortalities occur, were correlated with levels of inbreeding in St Kilda Soay sheep, using pedigree inbreeding coefficients and four marker-based estimators of inbreeding. None of the inbreeding estimators, either of the offspring, or of their mothers, explained significant variation in a lamb's birth weight or probability of surviving the neonatal period, suggesting low inbreeding depression for these traits. We evaluated the correlation between the marker-based measures of inbreeding and inbreeding coefficients obtained from the Soay pedigree, where paternal links were inferred using the same panel of microsatellite markers. Even when using a relatively complete portion of the pedigree, in which all individuals had known maternal and paternal grandparents, the correlation was found to be weak (r = −0.207, where mean f = 0.0168). These results add support to the recent prediction that when the mean and variance in inbreeding are low in a population, heterozygosity–fitness correlations can be very weak or even undetectable. The pursuit of more detailed pedigrees offers the best prospect for identifying inbreeding depression within this study population.
Original languageEnglish
Pages (from-to)3383-3393
Number of pages11
JournalMolecular Ecology
Volume14
Issue number11
DOIs
Publication statusPublished - Oct 2005

Fingerprint

Soay
inbreeding
heterozygosity
pedigree
sheep
inbreeding coefficient
inbreeding depression
birth weight
grandparents
lambs
microsatellite repeats
prediction

Keywords

  • birth weight
  • heterozygosity–fitness correlation
  • inbreeding depression
  • microsatellite
  • neonatal survival
  • Soay sheep

Cite this

Overall, Andrew ; Byrne, K.A. ; Pilkington, J.G. ; Pemberton, J.M. / Heterozygosity, inbreeding and neonatal traits in Soay sheep on St Kilda. In: Molecular Ecology. 2005 ; Vol. 14, No. 11. pp. 3383-3393.
@article{b99bba883f434d95b5c2ff10a51b0858,
title = "Heterozygosity, inbreeding and neonatal traits in Soay sheep on St Kilda",
abstract = "We investigated whether birth weight and neonatal survival, a period within which 24{\%} of all mortalities occur, were correlated with levels of inbreeding in St Kilda Soay sheep, using pedigree inbreeding coefficients and four marker-based estimators of inbreeding. None of the inbreeding estimators, either of the offspring, or of their mothers, explained significant variation in a lamb's birth weight or probability of surviving the neonatal period, suggesting low inbreeding depression for these traits. We evaluated the correlation between the marker-based measures of inbreeding and inbreeding coefficients obtained from the Soay pedigree, where paternal links were inferred using the same panel of microsatellite markers. Even when using a relatively complete portion of the pedigree, in which all individuals had known maternal and paternal grandparents, the correlation was found to be weak (r = −0.207, where mean f = 0.0168). These results add support to the recent prediction that when the mean and variance in inbreeding are low in a population, heterozygosity–fitness correlations can be very weak or even undetectable. The pursuit of more detailed pedigrees offers the best prospect for identifying inbreeding depression within this study population.",
keywords = "birth weight, heterozygosity–fitness correlation, inbreeding depression, microsatellite, neonatal survival, Soay sheep",
author = "Andrew Overall and K.A. Byrne and J.G. Pilkington and J.M. Pemberton",
year = "2005",
month = "10",
doi = "10.1111/j.1365-294X.2005.02682.x",
language = "English",
volume = "14",
pages = "3383--3393",
journal = "Molecular Ecology",
issn = "1365-294X",
number = "11",

}

Heterozygosity, inbreeding and neonatal traits in Soay sheep on St Kilda. / Overall, Andrew; Byrne, K.A.; Pilkington, J.G.; Pemberton, J.M.

In: Molecular Ecology, Vol. 14, No. 11, 10.2005, p. 3383-3393.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Heterozygosity, inbreeding and neonatal traits in Soay sheep on St Kilda

AU - Overall, Andrew

AU - Byrne, K.A.

AU - Pilkington, J.G.

AU - Pemberton, J.M.

PY - 2005/10

Y1 - 2005/10

N2 - We investigated whether birth weight and neonatal survival, a period within which 24% of all mortalities occur, were correlated with levels of inbreeding in St Kilda Soay sheep, using pedigree inbreeding coefficients and four marker-based estimators of inbreeding. None of the inbreeding estimators, either of the offspring, or of their mothers, explained significant variation in a lamb's birth weight or probability of surviving the neonatal period, suggesting low inbreeding depression for these traits. We evaluated the correlation between the marker-based measures of inbreeding and inbreeding coefficients obtained from the Soay pedigree, where paternal links were inferred using the same panel of microsatellite markers. Even when using a relatively complete portion of the pedigree, in which all individuals had known maternal and paternal grandparents, the correlation was found to be weak (r = −0.207, where mean f = 0.0168). These results add support to the recent prediction that when the mean and variance in inbreeding are low in a population, heterozygosity–fitness correlations can be very weak or even undetectable. The pursuit of more detailed pedigrees offers the best prospect for identifying inbreeding depression within this study population.

AB - We investigated whether birth weight and neonatal survival, a period within which 24% of all mortalities occur, were correlated with levels of inbreeding in St Kilda Soay sheep, using pedigree inbreeding coefficients and four marker-based estimators of inbreeding. None of the inbreeding estimators, either of the offspring, or of their mothers, explained significant variation in a lamb's birth weight or probability of surviving the neonatal period, suggesting low inbreeding depression for these traits. We evaluated the correlation between the marker-based measures of inbreeding and inbreeding coefficients obtained from the Soay pedigree, where paternal links were inferred using the same panel of microsatellite markers. Even when using a relatively complete portion of the pedigree, in which all individuals had known maternal and paternal grandparents, the correlation was found to be weak (r = −0.207, where mean f = 0.0168). These results add support to the recent prediction that when the mean and variance in inbreeding are low in a population, heterozygosity–fitness correlations can be very weak or even undetectable. The pursuit of more detailed pedigrees offers the best prospect for identifying inbreeding depression within this study population.

KW - birth weight

KW - heterozygosity–fitness correlation

KW - inbreeding depression

KW - microsatellite

KW - neonatal survival

KW - Soay sheep

U2 - 10.1111/j.1365-294X.2005.02682.x

DO - 10.1111/j.1365-294X.2005.02682.x

M3 - Article

VL - 14

SP - 3383

EP - 3393

JO - Molecular Ecology

JF - Molecular Ecology

SN - 1365-294X

IS - 11

ER -