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
ABSTRACT
Aim: The somatotropic axis (SA) comprises genes associated with economically important quantitative traits in livestock like mammary and muscle growth as well as carcass traits. Insulin growth factor-1 (IGF-1) and its receptor (IGF-1R) are two important genes belonging to the SA. The aim of this study was to evaluate the genetic polymorphism of IGF1/SnaBI and IGF-1R/TaqI restriction sites 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 250-bp fragment of the regulatory region of the buffalo IGF-1 gene and a 616-bp fragment of the IGF-1R gene encompassing 51-bp from exon 12, 479-bp from intron 12 and 86-bp from exon 13. The PCR-amplified fragments were digested with SnaBI (IGF-1) and TaqI (IGF-1R), electrophoresed and analyzed on agarose gels stained with ethidium bromide. The two amplified fragments were also sequenced and aligned with published sequences. Results: All buffaloes investigated in this study were genotyped BB (i.e., negative for the SnaBI restriction site at position 224