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Mapping QTL in Australian Dairy cattle using genomic selection methodologies
QTL affecting milk production were mapped using a Bayesian method that fits all 632,002 SNPs simultaneously in a population of 11,527 Holstein and 4687 Jersey animals. We identified 265 windows of 250 kb where the variance of predicted genetic value was > 50 times the variance of an average window. Windows were clustered into 42 regions across the genome. Based on their pattern of pleiotropic effects, we grouped these regions into 9 possible groups. We confirmed many known loci and highlight strong candidates in other regions. The observed pattern of QTL effects matched the known function in milk synthesis for some loci. Using a multi-breed population, fitting all SNPs simultaneously and studying QTL effects across multiple traits allowed separation of closely linked QTL and more precise positioning than previous single SNP regression methods.
Keywords:
GWAS
quantitative trait loci
pleiotropic effects
