Association of PIT-1 gene polymorphism with birth weight, milk and reproduction traits in Isfahan Holstein cows (Brief Report)

Abstract. Pit-1 (POU1F1) is a member of the POU-domain family of genes that play important regulatory roles in developmental processes (DYBUS et al. 2004). Pit-1, an approximate 33-kilodalton protein (291 amino acid), was first associated with a critical role in the transcriptional regulation of growth hormone (GH) and prolactin (PRL) genes (DYBUS et al. 2003). Molecular basis of this polymorphism was the silent mutation (G→A) located within exon 6 of the Pit-1 gene (DIERKES et al. 1998). Pit-1 gene considered as a candidate marker for milk production due to regulation of expression of bGH and the prolactin genes which are essential for mammary gland development and milk yield (DYBUS et al. 2004).