Effect of GnRHR, BMP6 and FSHR Gene Pyramiding on Litter Traits of Goats

Many studies have shown that only a few breeds of goat have the trait of high fertility, and genes play an important role in regulating litter size. This study investigated the effects of <i>GnRHR</i>, <i>BMP6</i>, and <i>FSHR</i> gene polymorphisms on litter traits in four goat breeds (Chongqing black, Chuanzhong black, Leizhou, and Nubian). Single nucleotide polymorphisms (SNPs) (g.75G > A in <i>GnRHR</i>, g.951T > C in <i>BMP6</i>, and g.-112C > T/g.3236C > A in <i>FSHR</i>) were genotyped using PCR-RFLP/HRM in 959 goats. Association analysis revealed significant correlations between these SNPs and litter size in the Chongqing, Chuanzhong, and Leizhou breeds, with genotypes AA (<i>GnRHR</i>), CC (<i>BMP6</i>), TT (<i>FSHR</i>), and AA (<i>FSHR</i>) linked to higher prolificacy. Polygene polymerizing effect analysis identified the optimal combinations (e.g., AATTCC, AACCAACC) with enhanced litter sizes. Tissue-specific qPCR in Chuanzhong goats showed <i>GnRHR</i>, <i>BMP6</i>, and <i>FSHR</i> were significantly more highly expressed in reproductive tissues (pituitary, breast, ovary, oviduct) of the prolific group than those in the non-prolific group. These SNPs serve as potential molecular markers for improving goat litter traits through polygenic selection, emphasizing the synergistic impact of multi-gene interactions on prolificacy.