Association between GH, PRL, LEP, and PIT-1 gene polymorphisms and growth traits in Indonesian Rambon indigenous cattle

For further understanding of the genetic control mechanisms of growth and development in cattle and to explore genetic marking loci that were associated with growth characteristics, we recruited a total of 31 Rambon indigenous cattle from Indonesia to detect 20 SNPs in growth hormone (GH), prolactin (PRL), leptin (LEP), and pituitary-specific transcription factor (PIT-1) by using direct sequencing techniques. From the results, we found that only SNP g.10976A > C in the PIT-1 gene was a non-synonymous mutation, which changed the amino acid from aspartic acid to alanine. The allele and genotype frequencies of all loci varied. Interestingly, the genotype frequencies of SNP g.7875A > G and g.8010C > T in the PRL gene and g.10958A > G in the PIT-1 gene were not under the Hardy-Weinberg equilibrium (P < 0.05). Of the identified mutations, SNP g.12238G > A of the LEP gene was significantly associated with body length (P < 0.05); SNPs g.10976A > C and g.11398A > C in the PIT-1 gene was significantly associated with body weight, chest girth, and shoulder height (P < 0.05). Interestingly, the heterozygous animals for the associated SNPs gained higher growth performances than the homozygous counterparts. No SNPs within the GH and PRL genes were associated with any traits (P > 0.05). These data suggest specific roles for GH and PRL polymorphisms in bovine growth traits and could be potential candidates for marker-assisted selection in the Rambon cattle population.