Study on Genetic Polymorphism of IGFBP-3 Gene in Egyptian Buffalo

Aim: The present work was carried out to study the genetic characteristics of the IGFBP-3 gene in buffaloes reared in Egypt, where it is considered as one of the important molecular markers for productivity traits like growth and immunity in livestock species. One-hundred animals were used in this research work. Methods: The studied gene was amplified through polymerase chain reaction technique. Afterwards, the amplified fragment at 651-bp was digested with three different endonucleases; HaeIII, MspI, and TaqI. The genetic character of the IGFBP-3 gene was studied by using PCR-RFLP and nucleotide sequencing. Results: The PCR products after the digestion with those restriction enzymes revealed that the presence of the following fragments: two fragments at 506- and 145-bp with MspI two fragments at 240- and 411-bp with TaqI; and eight fragments at 199-, 164-, 154-, 56-, 36-, 18-, 16- and 8-bp with HaeIII. The restriction digestion of the amplified fragments of the IGFBP-3 gene did not show a genetic polymorphism or nucleotide substitution where all restricted fragments yielded from the digestion with three restriction enzymes were of the same sizes. Conclusion: Our findings indicated that the absence of the genetic polymorphism of the IGFBP-3 gene in Egyptian buffalo. Based on our results in addition to the significant effect of this gene on different productivity traits, the crossing between Egyptian buffalo with other breeds, particularly the Italian breed, is needed for more improvements of Egyptian buffalo's productivity where the Italian buffaloes characterized by high growth and fertility phenomena.

Genetic Structure and Nucleotide Sequences of Three Productivity Trait Genes, in Egyptian Buffalo

One of the main sources of meat and milk in Egypt is buffalo, of river type. The marker assisted selection-depending on the promised genetic markers is considered to be the effective way for improvement of buffalo productivity. This work aimed to study the genetic structure and nucleotide sequences of three productivity genes namely; LGB, PIT-1, and POUF-1 in Egyptian buffalo. This study is performed by using genomic DNA, which was extracted from 100 female buffaloes. The DNA extracts were subjected to PCR by using some specific primers of the tested genes. The PCR products were digested with dedicated restriction enzymes like; HaeIII for LGB and HinfI for both PIT-1 and POUF-1 genes. Depending on the appearance of restriction sites in the amplified fragments; GG

Cytochrome b Diversity and Phylogeny of Six Egyptian Sheep Breeds

Aim: Cytochrome b (Cyt-b) regions of mtDNA have received more attention due to their role in the genetic diversity and phylogenetic studies in different livestock. By using Cytochrome b sequencing, we aimed to clarify the genetic affinities and phylogeny of six Egyptian sheep breeds. Methodology: The genomic DNA was extracted and the specific primers were used for conventional PCR amplification of the Cytochrome b region of mtDNA (1134-bp) in sheep. The alignment of sequences was done to identify the sequence variations and polymorphic sites in the amplified fragments. Results: The results showed the presence of 39 polymorphic sites leading to the formation of 29 haplotypes (accession numbers: MG407500 - MG407528) with total haplotype diversity 0.814 and nucleotide diversity 0.00359. The lowest genetic distance was observed between Rahmani and Saidi while the highest distance was observed between Ossimi and Sohagi. The sequences of 111 analyzed samples were aligned with reference sequences of different haplogroups; A, B, C, D and E. The result showed that 86 out of 111 tested animals cluster with haplogroup B (77.48%), whereas 12 tested animals cluster with each of both haplogroups A and C (10.81%) and one animal belongs to haplogroup E (0.90%) with the absence of haplogroup D. Conclusion: Cytochrome b regions of mtDNA have an important role in the genetic diversity and phylogenetic studies in farm animals as well as many other mammalian species.

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

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

Genetic Characterization of Insulin Growth Factor-1 and Its Receptor Genes in Egyptian Buffalo (Bubalus bubalis L.).

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