Genetic Polymorphisms in Exon-3 region of Growth Hormone Gene in the Egyptian Goat Breeds

Document Type : Original Article


1 Department of Cell Biology, Genetic Engineering Division, National Research Centre, Cairo, Egypt

2 Department of Chemistry, Faculty of Science, Cairo University, Cairo, Egypt

3 Department of Animal Production, Faculty of Agriculture, Cairo University, Cairo, Egypt


Background: In Egypt, the importance of goats comes from its potential source of meat and milk production. Thus, goat productivity improvement acts as a global strategy to provide Egyptians by important source of protein feeding. Molecular techniques have been employed to analyze growth hormone (GH) gene that promotes goat muscles, bone formation, regulating fat content and other important traits in goat. Our objective was to document and find out an accurate genetic marker sites, single nucleotide polymorphisms (SNPs) in exon-3 region of GH gene in some Egyptian goat breeds. Methods:  Fifteen blood samples were collected from three Egyptian goat breeds (Baladi, Barki and Zaraibi), DNA was isolated and primer was used to amplify GH gene region corresponding to exon-3 region. Finally, sequencing methodology was applied for PCR products regarding the three goat breeds. Results: The results showed four nucleotide substitutions; The first  SNP (CàT) was located at nucleotide position 106, the second SNP( GàA) was located at nucleotide position118 and the third  SNP (GàA) was located at nucleotide position 128 .Finally, the fourth  SNP (TàC) was located at nucleotide position 136. It was found that the SNP (GàA) at nucleotide position 128 caused an amino acid change from Glycine to Serine in the protein sequence of GH gene. Conclusion: Our findings demonstrated several genetic variations across exon-3 region of GH gene which can be used as marker in selection of goats with high valued traits.