Associations of six SNPs of POU1F1-PROP1-PITX1-SIX3 pathway genes with growth traits in two Chinese indigenous goat breeds

In the process of anterior pituitary gland development and maturation, numerous transcription factors were involved in the pituitary organogenesis. To date, the lack of knowledge on POU1F1-PROP1-PITX1-SIX3 pathway genes affecting growth traits was reported in Chinese goat breeds. The objective of this work was to identify genetic variants of the POU1F1, PROP1, PITX1 and SIX3 genes, as well as to evaluate their associations with growth traits in goats. The results showed that one novel and five reported single nucleotide polymorphisms (SNP) were confirmed in above four genes. The novel SNP (NC_019460.2:g.1100T>A) was located in intron 1 of SIX3 gene. Among these loci, DQ826397.1:g.102T>G (SNP1), DQ826397.1:g.279T>C (SNP2) and NC_019460.2:g.1100T>A (SNP6) were associated with growth traits. In details, the SNP1 locus had significant association with hucklebone width (P<0.05) and hucklebone width index (P<0.05) in the Guanzhong dairy goat. The SNP2 locus was associated with body weight (P<0.05), chest circumference (P<0.01), chest width (P<0.05), hucklebone width (P<0.05), cannon circumference (P<0.01) and trunk index (P<0.01) in the Hainan black goat. The SNP6 locus was significantly associated with hucklebone width index (P<0.05) and chest width (P<0.05) in the Guanzhong dairy goat and Hainan black goat, respectively. These findings indicated that goat POU1F1-PROP1-PITX1-SIX3 pathway genes were important genetic factors, which could affect growth traits. Three SNPs detected in this study may be useful for potential marker-assisted selection programs in goat breeding and production.