A PCR-RFLP investigation on PROP1 gene polymorphism and its association with milk production and growth traits in Mahabadi goats

Prophet of POU1F1 (PROP1) plays direct or indirect important roles in the morphogen- esis of pituitary gonadotropes as well as lactotropes, somatotropes and caudomedial thyrotropes. It also controls the expression of growth hormone, prolactin and thyrotropin subunits through regula- tory PIT1 factor. These hormones have important influences on production traits in most animal species including the goat. Therefore, PROP1 gene could be considered as a candidate gene for milk production. The objective of this study was to determine the polymorphism of PROP1 gene and its association with milk yield and growth traits in Mahabadi goats. We investigated the mutation (Gen- Bank accession number: AY533708.1) within exon 2 of PROP1 gene by using the Hin6I PCR-RFLP method.This polymorphism alters the amino acid at codon 79 from alanine to valine in PROP1 pro- tein. Only two genotypes CC and CT (frequencies 0.9 and 0.1 respectively) were observed. Poly- morphism of PROP1-Hin6I locus showed significant relationship with milk production (P < 0.01), milk fat percentage (P < 0.05), milk protein percentage (P < 0.05), somatic cell count (P < 0.05) and daily weight gain (P < 0.05). Therefore, PROP1-Hin6I locus could be considered as a molecular marker for milk production and milk composition traits in Mahabadi goats. Keywords: Mahabadi goat, association analysis, PROP1 gene, production traits