Parentage-based DNA traceback in beef and dairy cattle

Why is animal ID needed? Ways to physically label individual cattle Disputes arise even when animal identification systems are in place The dispute The resolution DNA is the label never removed from beef A chromosome has genes and other DNA Genes are encoded by sequences of DNA What are SNPs? Properties of SNPs Ways to use DNA for traceback Sometimes parentage testing is the last resort for DNA-based traceback Using SNP markers for parentage Accurate sire determination requires many DNA markers Comparing the calf to the sire: elimination Comparing the calf to a possible sire The ideal parentage SNP markers The ideal marker is frequent in all breeds The ideal markers are evenly distributed across the genome The ideal parentage marker scores accurately Accurate scoring requires that SNPs The nucleotide diversity in a typical region of the bovine genome The consequence of 1 SNP every 80 bp Bottom line: hidden SNPs may cause the wrong genotypes to be scored DNA sequencing strategy: nested PCR Parentage SNP population sequencing results Physical map of one region with a parentage SNP Immediate public access requested Public access to detailed SNP information Public internet access to flanking SNPs and allele frequencies by breed Individual animal genotypes linked to tracefiles Where are we now