High Throughput DNA Purification from Ear Punches, Blood, and Hair for Dairy Cattle Genetic Evaluation

DNA isolated from livestock can be used to identify genes influencing production traits, hair color, animal health, and viability. Breeders may provide hair, tissue, blood, or semen samples to genetic testing laboratories for DNA purification and analysis. Genetic markers and single-nucleotide polymorphism (SNP) genotypes can then be used in the genetic evaluation of these economic traits used in livestock selection.

We have developed an automated high throughput method on the KingFisher™ Flex instrument to purify DNA from dairy cattle ear punch tissue, blood, and hair samples using the ReliaPrep™ 96 gDNA Miniprep HT chemistry in a 96-well format. Ear punch tissue samples from test animals were collected using a Tissue Sampling Unit (TSU), blood samples were drawn in Vacutainer® Blood Collection Tubes (EDTA), and hair samples containing roots were collected from the cattle tail switch. Following Proteinase K digestion, sample lysates were added to 96-well plates and processed on the KingFisher™ Flex. The DNA purified was of high concentration, purity, and integrity necessary for downstream genetic analyses. Genotyping was conducted using Illumina Infinium Assay technologies with custom arrays. Call rates for DNA samples purified from tissue (26K Bovine SNP Array, n=287) and blood (140K Bovine SNP Array, n=67) were 99.75%, well above the minimum required to meet QC standards. 96 samples could be processed in about 2.5 hours, greatly reducing the possibility of identification error that can be associated with lengthy manual purification techniques.