A novel missense mutation (L280V) within POU1F1 gene strongly affects litter size and growth traits in goat

In mammals, POU1F1 is a key transcription factor that directly affects the secretion of pituitary hormones (GH, PRL, and TSH) and maintains growth and development. The aim of this study was to identify novel single nucleotide polymorphisms (SNPs) of the POU1F1 gene and evaluate the relations to litter size and growth performance in Shaanbei white cashmere (SBWC) goats. The ear tissues of female goats (n = 653) were collected, and the corresponding data were recorded. From direct DNA sequencing, a missense mutation (NC_030808.1:g.34236169A > C) was first detected in exon 6 of POU1F1 in SBWC goats that transformed the amino acid leucine into valine (L280V). Further analyses showed that the number of lambs of female goats with the TT genotype was significantly greater than that of female goats with the TG genotype (P < 0.01). In addition, a Chi-square test showed that the distributions of the two genotypes were remarkably different in the litters of two different sizes (P = 2.06E-06). Simultaneously, the frequency of the TT genotype for female goats with multiple lambs (≥2) was much greater than that of the TG genotype. When the relationships between growth traits and L280V were evaluated, the individuals with the TT genotype had superior growth traits compared with those of the TG genotype (P < 0.05), including for body height, body length, chest circumference, chest depth, chest width, height at hip cross, and cannon circumference. Notably, a positive relationship indicated that TT genotype female goats with improved growth traits tended to give birth to more lambs. We hypothesized that the mutation was in linkage disequilibrium with other responsible SNPs or affected the post-transcriptional regulation levels and then affected growth and litter size. This novel SNP may provide a functional genetic marker for improving economically valuable traits in goat breeding.