Identification of and genes polymorphisms in Hu sheep and their relationship with body size traits.

The body size traits are major traits in livestock, which intuitively displays the development of the animal's bones and muscles. This study used PCR amplification, Sanger sequencing, KASPar genotyping, and quantitative real-time reverse transcription PCR (qRT-PCR) to analyze the Single-nucleotide polymorphism and expression characteristics of Argonaute RISC catalytic component 2 () and Plectin () genes in Hu sheep. Two intron mutations were found in Hu sheep, which were g.51700 A > C and g.23157 C > T, respectively. Through association analysis of two mutation sites and body size traits, it was found that g.51700 A > C mainly affects the chest and cannon circumference of Hu sheep of while g.23157 C mainly affects body height and body length. The combined genotypes of and genes with body size traits showed SNPs at the g.51700 A > C and g.23157 C > T loci significantly improved the body size traits of Hu sheep. In addition, the gene has the highest expression levels in the heart, rumen, and tail fat, and the gene is highly expressed in the heart. These two loci can provide new research ideas for improving the body size traits of Hu sheep.