TGIF1andSF1polymorphisms are associated with litter size in Small Tail Han sheep

摘要

TGF-beta induced factor homeobox 1(TGIF1) andsplicing factor 1(SF1) are important for mammalian reproduction; however, the effects of these genes on litter size in sheep remain unexplored. In this study, we genotyped 768 ewes from seven sheep breeds at two loci: g.37871539C>T, a synonymous mutation ofTGIF1; and g.42314637T>C, a 3 ' UTR variant ofSF1. Our analysis of polymorphism revealed only two genotypes at locus g.37871539C>T inTGIF1, with most sheep populations being moderately polymorphic (0.25 < PIC < 0.5) at this site. In contrast, most breeds exhibited low polymorphism (PIC <= 0.25) at theSF1locus g.42314637T>C. The association analysis revealed that a synonymous mutation at g.37871539C>T inTGIF1was highly associated with litter size in Small Tail Han sheep, in which it causes a significant decrease in litter size. Conversely, while theSF13 ' UTR variant g.42314637T>C was also highly associated with litter size in sheep, it causes a significant increase in the number of litter size. Combined, these data provide valuable information regarding candidate genetic markers for sheep breeding programs.