An Association of Prolactin Gene Polymorphisms with Some Milk Traits in Women


  • Ahmed FA Department of Biology; College of Education for Pure Sciences; University of Basrah/Iraq
  • Ayied AY Department of Animal Resources; College of Agriculture; University of Basrah/Iraq
  • Awad NM Department of Animal Resources; College of Agriculture; University of Basrah/Iraq


We investigated the effects of prolactin gene polymorphisms on milk contents in women. The main aim of this work is to determine the genotypes of prolactin and its relationship with some milk chemical contents in women. Genotyping was carried out at Molecular Genetic Laboratory at the College of Agriculture, whereas biochemical assays were performed at the Department of Diseases Analyses at the South Technical University. Blood samples were collected for the prolactin-related gene. DNA was extracted from fifty candidate women. The extra-pituitary prolactin gene promoter 1149 G/T was subjected to XapI restriction enzyme. In this analysis   PRL-Pxa, I products result in three genotypes TT, TG and GG, as well as the population, is under Hardy-Weinberg equilibrium. Our results showed that the highest milk fat yield, milk protein, lactose and sold not fat (SNF) materials percentages were obtained by the genotype GG.


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How to Cite

FA, A., AY, A., & NM, A. (2018). An Association of Prolactin Gene Polymorphisms with Some Milk Traits in Women. American Scientific Research Journal for Engineering, Technology, and Sciences, 47(1), 21–27. Retrieved from