TY - JOUR
T1 - Epistatic quantitative trait loci affecting chemical body composition and deposition as well as feed intake and feed efficiency throughout the entire growth period of pigs
AU - Duthie, C-A
AU - Simm, G
AU - Doeschl-Wilson, AB
AU - Kalm, E
AU - Knap, PW
AU - Roehe, R
N1 - 1023378
PY - 2011
Y1 - 2011
N2 - Numerous quantitative trait loci (QTL) have been identified for growth and feed intake in pigs,
however, there are currently no reports of interactions between QTL (epistasis) for these traits
at different stages of growth. A genomic scan for epistatic QTL was conducted on animals from a
three generation full-sib population, created by crossing Pietrain sires with a crossbred dam
line. All types of two-locus interactions were fitted in the model using Cockerham's
decomposition, by regressing on a linear combination of the individual QTL origin probabilities.
This study is the first to report epistatic QTL for growth, feed intake and chemical body
composition in pigs. Eighteen significant epistatic QTL pairs were identified, seven affecting
growth, six affecting feed intake or food conversion ratio, and five affecting chemical body
composition. Most interacting QTL resided on different chromosomes; only two were located
on the same chromosome. The identified QTL pairs explained substantial proportions of the
phenotypic variance, from 5% to 10.3%. All types of digenic epistatic effects were identified with
the additive-by-additive effect being the most prevalent. These findings suggest that epistasis
is important in the genomic regulation of growth, feed intake and chemical body composition.
Furthermore, interactions occur between different pairs of epistatic QTL for the same trait
depending on the growth stage, increasing the complexity of genomic networks. This agrees
with studies on gene expression levels which showed that those are time and tissue dependent.
© 2010 Elsevier B.V. All rights reserved.
AB - Numerous quantitative trait loci (QTL) have been identified for growth and feed intake in pigs,
however, there are currently no reports of interactions between QTL (epistasis) for these traits
at different stages of growth. A genomic scan for epistatic QTL was conducted on animals from a
three generation full-sib population, created by crossing Pietrain sires with a crossbred dam
line. All types of two-locus interactions were fitted in the model using Cockerham's
decomposition, by regressing on a linear combination of the individual QTL origin probabilities.
This study is the first to report epistatic QTL for growth, feed intake and chemical body
composition in pigs. Eighteen significant epistatic QTL pairs were identified, seven affecting
growth, six affecting feed intake or food conversion ratio, and five affecting chemical body
composition. Most interacting QTL resided on different chromosomes; only two were located
on the same chromosome. The identified QTL pairs explained substantial proportions of the
phenotypic variance, from 5% to 10.3%. All types of digenic epistatic effects were identified with
the additive-by-additive effect being the most prevalent. These findings suggest that epistasis
is important in the genomic regulation of growth, feed intake and chemical body composition.
Furthermore, interactions occur between different pairs of epistatic QTL for the same trait
depending on the growth stage, increasing the complexity of genomic networks. This agrees
with studies on gene expression levels which showed that those are time and tissue dependent.
© 2010 Elsevier B.V. All rights reserved.
KW - Chemical body composition
KW - Epistasis
KW - Growth
KW - Pig
KW - Quantitative trait loci
U2 - http://dx.doi.org/10.1016/j.livsci.2010.11.022
DO - http://dx.doi.org/10.1016/j.livsci.2010.11.022
M3 - Article
VL - 138
SP - 34
EP - 48
JO - Livestock Science
JF - Livestock Science
SN - 1871-1413
ER -