association of novel polymorphisms in follicle stimulating hormone beta (fshβ) gene with litter size in mehraban sheep

Follicle-stimulating hormone (fsh) plays an important role in female reproduction by binding to a specific receptor (fshr) through the β-subunit of fsh on the surface of the ovarian granulosa cells. this study aimed to characterize the fsh β-subunit gene (fshβ) polymorphism and its association with litter size (ls) using a sample of 118 mehraban sheep. polymerase chain reaction (pcr) was performed to amplify fragments 300 bp and 431 bp of the ovine fshβ gene (oar_v4.0; chr 15, nc_019472.2). polymorphisms in the studied fragments were then explored using single strand conformational polymorphism (sscp) and dna sequencing methods. seven single-nucleotide polymorphisms (snps), including g.59078564 c>g, g.59078624 t>c, g.59078655 t>c, g.59078691 t>c, g.59078754 c>a, g.59080186 g>c and g.59080365 c>t, were found among the six detected sscp patterns a to f. moreover, two novel indel polymorphisms called e.g., g.59078702del8-bp−ins64-bp and g.59078726ins54-bp were identified among the three different sscp genotypes patterns g to i. we found significant differences in prolificacy categories between the sscp genotypes patterns d, e and f (p<0.01) that simultaneously represented snp polymorphisms of g.59078754 c>a, g.59080186 g>c and g.59080365 c>t. similarly, novel indel polymorphisms revealed a significant difference in prolificacy categories between the sscp genotypes patterns g, h and i (p<0.05). our results suggested that fshβ is a strong candidate gene to associate with the ls in sheep.