Showing 3 results for Polymorphism
Gh. Elyasi, Dj. Shodja, M.r. Nassiry, A. Tahmasebi, O. Pirahary,
Volume 9, Issue 2 (7-2005)
Abstract
In modern programmes of animal breeding, the polymorphisms of the milk proteins can be used as marker systems. Beta-Lactoglobulin is the major milk whey protein in the ruminants. The BLG coding gene located on ovine chromosome 3. This protein, synthesis in the mammary glands during pregnancy and the lactation stages. Studies have indicated that this protein is polymorphic in the many breeds of sheep. This is the result of a single base pair substitution in the Beta-Lactoglobulin gene that also rises to the RsaI restriction fragment length polymorphism (RFLP). The aim of this work was to analyze the genotype distribution of Beta-Lactoglobulin in sheep. Blood samples were supplied from 142 sheep of the 5 breeds (Ghezel, Afshari, Moghani, Makoii and Arkharmerino). Genomic DNA was extracted from the 200ul blood sample according to Boom et al. (1989) method modified by Shaikhayev (1995). The Gel monitoring and the spectrophotometeric methods were used for determination of the DNA quality and quantity. the Primers BLG5 and BLG3 amplified a 452 bp fragment from the exon II of the ovine Beta-Lactoglobulin gene. the Products of the amplification were recognized by the electrophoresis on the 1% agarose gel stained with ethidium bromide. The RsaI enzyme was used for restriction of the PCR products. The digested products were separated by the electrophoresis on the 8% nondenaturant polyacrylamide gel and visualized after staining with the ethidium bromide on UV transillumination. The popGen32 software (ver.1.31) was used to estimate the allele and the genotype frequencies, the Hardy-Weinberg equilibrium and dendrogram of the genetic distance. The frequency of A-allele in Ghezel, Afshari, Moghani, Makoii and Arkharmerino breeds was 56%, 34%, 36%, 53% and 48% respectively. The populations were in Hardy-Weinberg equilibrium except to Afshari breed. The lowest genetic distance was observed between Moghani and Afshari breeds and the highest genetic distance between Ghezel and Afshari breeds. The results of this study indicated that PCR-RFLP is an appropriate tool for evaluating genetic variability in sheep.
M. H. Banabazi, S. Esmaeilkhanian, S. R. Miraei Ashtiani, M. Moradi Shahrbabak,
Volume 10, Issue 4 (1-2007)
Abstract
Genetic variation within and between five Iranian sheep populations including Sanjabi (SAN), Kordi Kordistan (KKO), Kordi Khorasan (KKH), Mehraban (MEH) and Moghani (MOG) was assessed using six microsatellite markers (McMA2, McMA26, MAF64, OarAE64, OarCP26 and OarFCB304). The PCR reactions were successfully perfomed with all primers except OarAE64. All locus-population combinations were at Hardy-Weinberg equilibrium except McMA2 in MOG population (P<0.005). Polymorphism criteria showed that the five studied loci were polymorphic in all populations. The lowest DA genetic distance (0.234) was observed between KKH and KKO and the highest (0.388) between SAN and MOG populations. The dendrograms based on DA distances were drawn using unweighted pair-group method using an arithmetic average (UPGMA) and neighbor-joining (NJ) method. KKO, KKH and SAN were grouped together at one cluster and MEH and MOG at another by both methods. The average expected heterozygosity for each populations (as interpopulation variation) ranged from 0.744 to 0.847 for KKH and MEH, respectively. The estimated time of divergence for two Kordi populations (KKO and KKH) was 445 years that complies with historical evidences. The findings of this research confirmed that microsatellite variation could be a useful tool for screening of investigating biodiversity among domestic animals.
S. Esmail Khanian, A. Negati Javaremi, F. Afraz, P. Daneshyar, S. Ghanbari,
Volume 11, Issue 41 (10-2007)
Abstract
In order to identify polymorphic microsatellite markers and evaluae genetic variation within Baluchi sheep population, nineteen microsatellite loci were studied. Whole Blood samples were collected from 156 sheep at north eastern animal breeding station of Iran (Abbasabad-Mashhad). DNA was extracted by salting-out procedure with some modifications. Polymerase chain reactions were successfully done except for UNC5C locus. PCR products were electrophoresed on 8% denaturing polyacrylamide gels stained according to rapid silver staining procedure. The genotype and allelic frequencies were calculated by direct counting and used for estimating of different polymorphism and genetic variation criteria. This population wasn't at Hardy-Weinberg equilibrium except for OarAE101 locus (P<0.005). Heterozygosity (gene variation) ranged from 0.1 to 0.93. BULGE5E and BM1329 loci were monomorphic. In conclusion, this investigation showed high polymorphism at the studied loci, so they could be used in future studies.
