S.  Tavakoli, J.  Fayazil, T.  Hartatik, Z.  Biranvand, M.T.  Beigi Nassiri, 
    The Study of <I>PIT1</I> Gene Polymorphism in the Najdi Cattle Using PCR-RFLP Method,
    Journal of Animal and Veterinary Advances,
    Volume 9,Issue 15,
    2010,
    Pages 2001-2003,
    ISSN 1680-5593,
    javaa.2010.2001.2003,
    (https://makhillpublications.co/view-article.php?doi=javaa.2010.2001.2003)
    Abstract: The part of the bovine genome which shows a superior action and explains the major part of variation of the economical production traits were known as QTL. <I>PIT1</I> gene which is also termed hormone factor-1 is a pituitary-specific transcription factor which has responsible for pituitary development and hormone expression in mammals. The main function of <I>PIT1</I> is for binding and trans-activity promoters of both Growth Hormone (GH) and Prolactin (PRL) gene. It was subjected to different molecular studies as a key role for understanding genetic variation in dairy cattle. This study was aimed to detect the polymorphism in a part of <I>PIT1</I> gene, exon 6 in Najdi cattle. DNA was extracted from blood sample collected from 84 Najdi Cattle and submitted for Polymerase Chain Reaction (PCR) followed by digestion with <I>HinfI</I> restriction enzyme. Base on PCR-RFLP method, it found that the frequency of the A and B alleles of this gene for Najdi Cattle were 18.45 and 81.55%, respectively. The genotypic frequencies of AA, AB and BB were 3.57, 29.76 and 66.66%, respectively. &#967;<SUP>2</SUP>-test indicated that these two populations were at Hardy-Weinberg equilibrium. Thus, the selection base on these loci in the population is possible to be done.
    Keywords: growth harmone;allele;najdi cattle;polymorphism;PIT1 gene;prolactin