Abstract :
The physiological effects of prolactin-releasing peptide (PrRP) are not only able to mediate
prolactin secretion but also regulate food intake and energy homeostasis. Thus the PrRP
gene is an important potential candidate gene for production performance in livestock.
Here, we firstly explored the DNA sequence of the PrRP gene, the genomic organization and
the genetic variants. The caprine PrRP gene is organized in two exons and is transcribed into
an mRNA containing 297 bp of sequence coding for a protein of 98 amino acids. Its protein
sequences showed substantial similarity, 97%, to its orthologs from cattle and sheep. Four
sequence variants including three SNPs and a large insert mutation were identified in the
study of four different goat populations consisting of 1408 healthy and unrelated individuals.
Seven haplotypes involving four sequence variant sites in the caprine PrRP gene were
identified and their effects on production traits were analyzed. The results revealed that
haplotype 1 had the highest haplotype frequencies in the dairy populations and was highly
significantly associated with body length (P < 0.01), chest circumference (P < 0.01) and milk
yield (P < 0.05) in the analyzed populations, respectively. Our results provide evidence that
polymorphisms in the PrRP gene are associated with production traits, and may be used for
marker-assisted selection and management in goat breeding programs
