Genome-wide SNP discovery and genetic diversity evaluation of Liangshan cattle in China

Liangshan cattle are a very small indigenous breed with adult weight of less than 300 Kg and have been mainly distributed in the Liangshan Yi Autonomous Prefecture of Southwestern Sichuan, China. Due to its long-term adaptation to local environments, Liangshan cattle is a valuable genetic resource and should be paid with more attentions. However, the genetic diversity of Liangshan cattle have not been specifically investigated yet, which would be required when designing the appropriate conservation and utilization programs. In this study, we successfully employed the restriction-site-associated DNA sequencing (RAD-seq) approach to explore a total of 84,854 genome-wide and high-confidence SNPs of Liangshan cattle. All these SNPs were evenly distributed through all chromosomes with an average of 98 SNPs per 1-Mb region. The nucleotide diversity, expected heterozygosity, polymorphism information content of Liangshan cattle were 0.227, 0.223 and 0.183, respectively. Furthermore, there was no obvious difference on the genetic diversity among the three studied geographical populations. In conclusion, we provided a list of SNPs that could be used in the follow-up studies for Liangshan cattle and revealed a relatively high genetic variation in this gene pool.