Genotyping and Nucleotide Sequences of Growth Hormone Releasing Hormone and Its Receptor Genes in Egyptian Buffalo.

ABSTRACT

Aim: The hypothalamic hormone, growth hormone-releasing hormone, is the principal stimulator of pituitary growth hormone (GH) synthesis and secretion. GHRH and its receptor (GHRHR) provide important functions in the regulation of the GH axis and in the development and proliferation of pituitary somatotropic axis. This study aimed to identify the genotypes and nucleotide sequences of two multifunctional genes; growth hormone-releasing hormone (GHRH) and its receptor (GHRHR) in Egyptian buffalo. Methodology: Genomic DNA was extracted from blood samples of 100 healthy buffaloes maintained at the Mahlet Mussa and El-Gmeasa herds from 2010 to 2012. PCR was performed using primers flanking a 296-bp fragment from GHRH gene and a 425-bp fragment from GHRHR gene of Egyptian buffalo. The PCR-amplified fragments were digested with HaeIII (GHRH) and Eco57I (GHRHR), electrophoresed and analyzed on agarose gels stained with ethidium bromide. The two amplified fragments were also sequenced and aligned with published sequences. Results: Depending on the presence of the restriction site at 241