GENOTOXIC AND CARCINOGENIC STUDIES OF NORGESTREL IN DROSOPHILA MELANOGASTER

Objective: The aim of this study was to investigate, for the first time, the possible in vivo genotoxic and carcinogenic activity associated with exposure to norgestrel (NGT) drug through employing the very recently established and adjusted genotoxic and tumorigenic methods in Drosophila melanogaster.Methods: Two in vivo genotoxic test systems were used; one detects the somatic mutation and recombination effects (somatic mutation and recombination test [SMART] wing-spot test) and the other detects the primary DNA damage (the comet test) in the body cells of D. melanogaster. On the other hand, the warts (wts)-based SMART assay is a vital genetic examination in Drosophila used to identify and characterize cancer potential of compounds.Results: Four experimental doses of NGT were used (ranging from 0.24 μM to 16 μM). NGT was found to be non-genotoxic at all tested concentrations even at the highest dose level 16 μM and failed to increase the frequency of tumors in the somatic cells of D. melanogaster.Conclusion: Our results strengthen the hypothesis that steroidal drugs might act through a non-genotoxic carcinogen mechanism where the carcinogenic properties occur by direct stimulation of cellular proliferation through a steroid receptor-mediated mechanism. In addition, the results obtained in this research work may contribute to highlighting the importance of NGT as a potent neuroprotective antioxidant drug

DNA Characterization and Polymorphism of KISS1 Gene in Egyptian Small Ruminant Breeds

Genetic information especially of the Quantitative Trait Loci (QTL) which affect different performance traits is considered one of the most effective tools in the breeding programs of livestock. Several genes were reported as candidate genes that effect litter size performance and one of these genes is the KISS1 which is considered as a regulator of puberty onset. The polymorphisms of KISS1 gene have some relationships with high prolific and sexual precocity. The objective of this study was the detection of the restriction fragment length polymorphism (RFLP) and single nucleotide polymorphisms (SNPs) of KISS1 gene in six major Egyptian small ruminant breeds. The primers used in this study flanked a 377 bp fragment from intron 1 of KISS1 gene in sheep and goat. These PCR amplified fragments were digested with XmnI endonuclease. According to the presence or absence of the restriction site (GAANN^NNTTC) at position 121^122, we genotyped the 122 tested animals as AT (54.92%) and TT (45.08) with the absence of AA genotype. The overall frequencies of alleles A and T were 27.46 and 72.54%, respectively. The sequence analysis of purified PCR products representing these two detected genotypes declared the presence of a SNP (T→A) at position 125 in the amplified fragment which is responsible for the elimination of the restriction site and consequently the presence of two different alleles T and A. The nucleotide sequences of sheep KISS1 alleles T and A as well as goat KISS1 alleles T and A were submitted to GenBank database and have accession numbers: KP835797, KP835798, KP835799 and KP835800, respectively. It is concluded that small ruminant breeds have high frequency of KISS1 allele T which was associated with greater litter size. We recommend to increase this allele in Egyptian small ruminant breeds and also to select the animals which possess TT genotypes of KISS1 gene and enter them in breeding programs of Egyptian small ruminants to increase their fecundity traits.Keywords: Sheep, Goat, KISS1, Polymerase Chain Reaction (PCR), Restriction Fragment Length Polymorphism (RFLP), Single Nucleotide Polymorphisms (SNPs

New polymorphism in the 5′ flanking region of IGF-1 gene and its association with wool traits in Egyptian Barki sheep

Insulin-like growth factor-1 gene (IGF-1) is considered as a major candidate gene for the economic traits of animal production. Polymorphism of 5′ flanking region of IGF-1 gene in Barki sheep (n = 91) and its association with wool traits were studied using the polymerase chain reaction coupled with single-strand conformation polymorphism technique (PCR-SSCP), PCR-restriction fragment length polymorphism (PCR-RFLP), sequence analysis and different measurements of wool traits (clean fleece weight and fiber diameter). PCR-SSCP analysis revealed three different banding patterns corresponding with three genotypes frequencies GG (0.25), GA (0.58), AA (0.17). PCR-RFLP and corresponding sequence analysis revealed nucleotide transversion from Guanine (G) to Cytosine (C) at nucleotide position 85 and transition from (G) to Adenine (A) at position 87. This is the first study that recorded two SNPs within the 5′ flanking region of IGF-1 gene in Egyptian Barki sheep, which were submitted to DNA Data Bank OF Japan (DDBJ) with Accession No. LC151463.1. The genotype GG showed positive significant association (P  0.05) with different IGF-1 genotypes. This study adds evidence of the association between IGF-1 gene polymorphism and CFW of wool in Egyptian Barki sheep. Therefore; it is important to consider IGF-1 gene as a candidate gene marker for wool weight traits and it should be identified before using successful breeding program