Establishment and optimization of the DNA extraction from yak milk

A reliable and rapid method for genomic DNA extraction was constructed here to accelerate the identification of important genes in yak.In this method,the yak milk was first centrifuged,and then somatic cells were obtained for DNA extraction.The influences of different methods of protein removal,DNA precipitants,and storage conditions of yak milk on DNA quality were discussed.The quality of DNA was detected using PCR.Experimental results indicated that both the salting-out and phenol-chloroform method were effective for the removal of proteins,however the salting-out method was more simple and rapid.The precipitants isopropyl alcohol and ethanol were similar to precipitate DNA,but the glycol ether was the worst precipitant in this study.The storage conditions of yak milk have remarkable influence on the quality of DNA,and when the yak milk was stored at 4 ℃ for short term,or-20 ℃ for long term,the desired DNA can be got.The DNA extracted from yak milk using the salting-out method can be used in the later genetic research.