SNP of gene in three cattle breeds using snapshot technology.

Droughtmaster is a tropical breed of beef cattle that can survive in hot climates and easily adapt to torrid environments. These traits are important in livestock breeding. In this study, we genotyped five single-nucleotide polymorphisms (SNPs) of the gene from 190 cattle belonging to three different breeds (Droughtmaster, Angus and Simmental) by using snapshot technology. This work aimed to identify the valuable molecular marker of heat resistance in cattle. Results showed that Droughtmaster exhibited higher expected heterozygosity and polymorphic information content compared with the two other breeds. The -1 locus deviated from the Hardy-Weinberg equilibrium in the Droughtmaster breed (P < 0.05). Two SNPs in Droughtmaster diverged significantly from Angus and Simmental. The SNPs were identified as -3 and -4, which were closely linked to the three breeds based on pair-wise FST. -4 involved a missense mutation. In summary, the GG genotypes in -3 and -4 may be candidate genotypes associated with heat resistance traits and may serve as valuable genetic markers for breeding of heat-tolerant beef cattle in the future.