A Single Nucleotide Polymorphism in the Acetyl-coenzyme A Acyltransferase 2 (ACAA2) Gene is Associated With Milk Yield in Chios Sheep
Journal
Journal of Dairy Science
Date Issued
June 2012
DOI
10.3168/jds.2011-4732
Abstract
The objective of this work was to identify single
nucleotide polymorphisms (SNP) in the ovine acetylcoenzyme
A acyltransferase 2 (ACAA2) gene and
investigate their association with milk production
traits. Molecular characterization was accomplished by
sequencing the entire coding region and the 3 and 5
untranslated regions (UTR) of the ACAA2 gene from
individuals of the Chios sheep bred in Cyprus. All exons
appeared to be monomorphic except for the last
exon, for which a single SNP located in the 3 UTR of
the gene (HM537015:g.2982T>C) was detected. Mixed
model association analysis, using SNP data from 318
animals from 104 paternal half-sib families and firstlactation
phenotype and pedigree information on 2,405
ewes revealed that this SNP was significantly associated
with milk yield. The significance of the SNP effect
persisted when milk yield information up to the third
lactation was analyzed. Both alleles at the locus segregated
at similar frequencies. The T allele was associated
with increased milk yield and exhibited partial dominant
action. Animals with the g.2982TT or g.2982CT
genotype had significantly higher milk yield than those
with the g.2982CC genotype, with the g.2982T allele
having an additive effect of 13.4 (±4.7) kg and a dominance
effect of 7.9 (±6.1) kg. Based on estimated allelic
effects and sample allele frequencies, the g.2982T>C
SNP explained 10% of the additive genetic variance for
milk yield. A putative mode of action through nutrient
metabolism is discussed.
nucleotide polymorphisms (SNP) in the ovine acetylcoenzyme
A acyltransferase 2 (ACAA2) gene and
investigate their association with milk production
traits. Molecular characterization was accomplished by
sequencing the entire coding region and the 3 and 5
untranslated regions (UTR) of the ACAA2 gene from
individuals of the Chios sheep bred in Cyprus. All exons
appeared to be monomorphic except for the last
exon, for which a single SNP located in the 3 UTR of
the gene (HM537015:g.2982T>C) was detected. Mixed
model association analysis, using SNP data from 318
animals from 104 paternal half-sib families and firstlactation
phenotype and pedigree information on 2,405
ewes revealed that this SNP was significantly associated
with milk yield. The significance of the SNP effect
persisted when milk yield information up to the third
lactation was analyzed. Both alleles at the locus segregated
at similar frequencies. The T allele was associated
with increased milk yield and exhibited partial dominant
action. Animals with the g.2982TT or g.2982CT
genotype had significantly higher milk yield than those
with the g.2982CC genotype, with the g.2982T allele
having an additive effect of 13.4 (±4.7) kg and a dominance
effect of 7.9 (±6.1) kg. Based on estimated allelic
effects and sample allele frequencies, the g.2982T>C
SNP explained 10% of the additive genetic variance for
milk yield. A putative mode of action through nutrient
metabolism is discussed.