Study of polymorphism of Growth Hormone-releasing Hormone (GHRH) Alleles in Iranian Sarabi Cows

Subject Areas : Veterinary Clinical Pathology

mehdi  khosravi ¹ (دانشگاه آزاد اسلامی، واحد علوم وتحقیقات تهران، گروه علوم دامی، تهران، ایران.)
mehdi  aminafshar ² (دانشگاه آزاد اسلامی، واحد علوم وتحقیقات تهران، گروه علوم دامی، تهران، ایران.)
mohammad  chamani ³ (دانشگاه آزاد اسلامی، واحد علوم وتحقیقات تهران، گروه علوم دامی، تهران، ایران.)

Received: 2013-07-07 Accepted : 2013-11-14 Published : 2013-08-23

Keywords: polymorphism, : Sarabi cows, <i>GHRH<i>,

Abstract :

Selection based on molecular markers is one of the new methods that may improve progress and accuracy of selection in animal breeding programs. The GHRH gene (Growth Hormone-releasing Hormone) is a candidate gene for marker-assisted selection strategies. Polymorphs of GHRH gene are reported to be significantly associated with milk production and constituent traits. In order to study the polymorphism of GHRH gene, blood samples were collected from 112 Sarabi cows. Genomic DNA was extracted and a fragment of 297 bp in size was amplified using polymerase chain reaction. The amplified fragments were subjected to restriction digestion with HaeIII endonuclease enzyme and the resultant digested products were run on 2% Agarose gel. The results revealed the existence of two alleles of GHRH A&nbsp;and GHRH B&nbsp;for the examined locus with frequencies of 0.19 and 0.81 respectively. Three different genotypic variants including GHRH A&nbsp;GHRH A, GHRH A&nbsp;GHRH B&nbsp;and GHRH B&nbsp;GHRH B&nbsp;were identified with genotypic frequencies of 0.0357, 0.3037 and 0.6607 respectively. The &chi;2 test showed that population is in Hardy-Weinberg equilibrium (P&lt;0.05). These data provide evidence that sarabi cattle breed have a genetic variability, which opens interesting prospects for future selection programs, especially marker-assistant selection.

References:

• عصری، م. (1380). همایش گاو و گاومیش؛ نقطه تلاقی علم و تجربه. مجله دامداران ایران، دوره 27،  شماره 3، صفحه 71-65.


• تربتی، ف. (1383). بررسی پلی‌مورفیسم و فراوانی آللی اگزون 2 در جایگاه ژنی BoLA-DRB3 در گاوهای نجدی و سرابی، پایان‌نامه کارشناسی ارشد، دانشکده کشاورزی. دانشگاه فردوسی.

 

• Asri, M. (2002). Conference of cattle and buffaloes: Intersection of science and experience. Journal of Iranian farmers, 27(3): 65-71 [In Farsi].


• Barendse, W., Armitage, S.M. and Kossarek, L.M (1994). A genetic linkage map of the bovine genome. Nature Genetics, 6: 227-235.


• Boom, R., Sol, C.J.A., Salimans, M.M.M., Jansen, C.L., Wertheim-Van Dillen, P.M.E. and Van Der Noordaa, J. (1989). Rapid and simple method for purification of nucleic acids. Journal of Clinical Microbiology, 28(3): 495-503.


• Dybus, A. and Grzesiak, W. (2006). GHRH/HaeIII gene polymorphism and its associations with milk production traits in Polish Black-and-White cattle Arch. Tierz, Dummerstorf, 49(5): 434-438.


• Dybus. A., Kmiec, M., Sobek, Z. and Pietrzyk, W. (2003). Associations between polymorphisms of growth hormone releasing hormone (GHRH) and pituitary transcription factor 1 (PIT1) genes and production traits of Limousine cattle. Arch. Tierz, Dummerstorf, 46(6): 527-534.


• Frohman, L.A., Bowns, T.R. and Chomeszynski, P. (1992). Regulation of growth hormone secretion. Front. Neuroendocrinology, 13: 344 - 405.


• Kmiec, M., Luczak, I.K., Kulig, H. and Terman, A. (2007). Associations between GHTH/HaeIII restriction polymorphism and milk production traits in a herd of dairy cattle. Journal of Animal and Veterinary Advances, 6(11): 1298-1303.


• Moody, D.E., Pomp, D. and Barendse, W. (1995). Restriction fragment length polymorphism in amplification products of the bovine growth hormone-releasing hormone gene. Journal of Animal Science, 73: 37-89.


• Torbati, F. (2005). Study of polymorphism of Bovine Lymphocyte Antigen DRB3.2 Alleles in Najdi and Sarabi Cows. M.Sc. thesis. College of Agriculture, Ferdowsi University, Mashhad-Iran [In Farsi].


• Zhou, P., Kazmer, G.W. and Yang, X. (2000). Bos taurus growth hormone releasing hormone gene, complete cds. GenBank, AF 24: 28-55.