• Journal of Plant Biotechnology
• /
• 제5권4호
• /
• pp.201-207
• /
• 2003

Tissue culture techniques arguably are an important approach for ex situ conservation of rare and endangered plant species. However, there is utmost importance on maintaining the genetic integrity of the introduced plants especially in tree species. To examine the genetic integrity of the micropropagated plants, we randomly screened few hardened plants of Syzygium travancoricum, a critically endangered tree taxon, using Randomly Amplified Polymorphic DNA (RAPD) markers. Twenty-three random. primers were tried and twenty-five polymorphic loci were identified. The dendrogram based on the Unweighted Pair-Group Method Arithmetic Average and Nei's similarity index depicted about 97% homology between the mother plants and micropropagated plants. Further, an attempt was made to reintroduce the micropropagated plants in the wild. Over three hundred small trees could be successfully established.

• Journal of Plant Biology
• /
• 제37권3호
• /
• pp.277-284
• /
• 1994

I investigated levels of genetic diversity, population genetic structure, and gene flow in Hostacapitata, a herbaceous perennial native to South Korea and southwestern Japan. Starch gel electrophoresis was conducted on leaves collected from 310 plants in 19 Korean populations. Twenty-two of 25 putative loci examined were polymorphic in at least one populatin and the mean number of alleles per locus was 1.65. In addition, mean expected heterozygosity within populations (Hep=0.153) was higher than average values for species with similar life history traits. Significant differences in allele frequency were detected between populations at all loci (P<0.01), and slightly over 30% of the genetic variation was found among populatins (GST=0.308). Indirect estimates of the number of migrants per generation (Nm) (0.506, calculated from GST; 0.852, calculated from the mean frequency of ten private alleles) indicate that gene flow is restricted among the isolated Korean populations of H. capitata. Factors contributing to the high levels of genetic differentiation among populations of H. capitata include small and discrete populations, human disturbance, and low frequencies of pollinator foraging behavior.

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권3호
• /
• pp.302-306
• /
• 2001

This study was carried out to construct mapping population and to evaluate the methods involved, including polymorphic DNA marker system and appropriate statistical analysis. As an initial step to establish chicken genome mapping project, White Leghorn (WL) and Korean Ogol chicken (KOC) were used for generating backcross population. From 8 initial parents, total 280 backcross progenies were obtained and 40 were used for genotyping and linkage analysis. For development of novel polymorphic markers for KOC, Random Amplified Polymorphic DNA (RAPD) markers specific for this chicken line were generated. Also included in this study were six microsatellite markers from East Lansing map as reference loci. For segregation analysis, 15 RAPD markers and 6 microsatellites were used to genotype the backcross population. Among the RAPD markers that we developed, 2 pairs of markers were identified to be linked and another 4 RAPD markers showed linkage with microsatellites of known map. In summary, this study showed that our backcross population generated from the mating of KOC to WL serves as a valuable genetic resource for genotyping. Furthermore, RAPD markers are proved to be valuable in linkage mapping analysis.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권11호
• /
• pp.1556-1560
• /
• 2006

Six breeds of riverine buffalo viz. Murrah, Mehsana, Jaffrabadi, Nagpuri, Nili-Ravi and Bhadawari were characterized using FAO-recommended cattle specific microsatellite markers. Among the total of twenty microsatellite markers screened to explore genomic variability of six buffalo breeds, only ten were polymorphic in nature. Four out of ten polymorphic microsatellite loci were rated as informative. The numbers of alleles detected ranged from 2 to 7, with a mean of $5.5{\pm}0.07$ per microsatellite marker. The most polymorphic marker was BM1818 with a total of 7 alleles present at this locus. One breed specific marker was found in each of Mehsana (BM1818) and Bhadawari (ILSTS030) and four were found in Jaffarabadi (BM1818, ILSTS030, ILSTS054 and ILSTS011). Genetic distance (Ds) between the Mehsana and Bhadawari breed was the maximum (0.29), followed by Murrah and Mehsana (0.27), and Nili-Ravi and Bhadawari (0.26). The lowest Ds was found between the Jaffrabadi and Nagpuri breeds which was only 0.05. The highest divergence time of 1318 years was established between Mehsana and Bhadawari breeds whereas it was found to be lowest (272 years) between the Jaffrabadi and Nagpuri breeds.

• Asian-Australasian Journal of Animal Sciences
• /
• 제25권1호
• /
• pp.28-32
• /
• 2012

In the present study, we evaluated the informativeness of SNPs genotyped by the Illumina Bovine SNP50K assay in different cattle breeds. To investigate these on a genome-wide scale, we considered 52,678 SNPs spanning the whole autosomal and X chromosomes in cattle. Our study samples consists of six different cattle breeds. Across the breeds approximately 72 and 6% SNPs were found polymorphic and fixed or close to fix in all the breeds, respectively. The variations in the average minor allele frequency (MAF) were significantly different between the breeds studied. The level of average MAF observed in Hanwoo was significantly lower than the other breeds. Hanwoo breed also displayed the lowest number of polymorphic SNPs across all the chromosomes. More importantly, this study indicated that the Bovine SNP50K assay will have reduced power for genome-wide association studies in Hanwoo as compared to other cattle breeds. Overall, the Bovine SNP50K assay described in this study offer a useful genotyping platform for mapping quantitative trait loci (QTLs) in the cattle breeds. The assay data represent a vast and generally untapped resource to assist the investigation of the complex production traits and the development of marker-assisted selection programs.

• 한국육종학회지
• /
• 제43권1호
• /
• pp.14-22
• /
• 2011

In this study, 15 simple sequence repeat (SSR) markers were used to analyze the population structure of 55 mungbean accessions (34 from South Asia, 20 from West Asia, 1 sample from East Asia). A total of 56 alleles were detected, with an average of 3.73 per locus. The mean of major allele frequency, expected heterozygosity and polymorphic information content for 15 SSR loci were 0.72, 0.07 and 0.33 respectively. The mean of major allele frequency was 0.79 for South Asia, and 0.74 for West Asia. The mean of genetic diversity and polymorphic information content were almost similar for South Asian and West Asian accessions (genetic diversity 0.35 and polymorphic information content 0.29). Model-based structure analysis revealed the presence of three clusters based on genetic distance. Accessions were clearly assigned to a single cluster in which >70% of their inferred ancestry was derived from one of the model-based populations. 47 accessions (85.56%) showed membership with the clusters and 8 accessions (14.54%) were categorized as admixture. The results could be used to understanding the genetic structure of mungbean cultivars from these regions and to support effective breeding programs to broaden the genetic basis of mungbean varieties.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제5권2호
• /
• pp.205-211
• /
• 2002

Previously, genetic relationships among 321 silkworm races preserved in the Department of Sericulture and Entomology, NIAST, RDA were studied using six isozymes comprising 20 loci. As a part of additional studies, three additional isozymes with 7 loci [phos-phoglucomutase (PGM), glucose phosphate isomerase (GPI), malete dehydrogenase (MDH)] from hemolymphs, midgets, and eggs were employed to reevaluate the previous dendrogram (UPGMA method). Although the current study supported the recognition of the previously identified major groups, some minor changes were apparent among the selected 47 forms. The current study showed that the polymorphic loci of GPI from eggs and MDH from hemolymph appear to be responsible characters for generating a new major group in the genetic relationship. Interpreting the data with current additive isozymes may represent more robust genetic relatioships among 321 silkworm races preserved in Korea, until further evidence is available.

• 한국패류학회지
• /
• 제11권1호
• /
• pp.51-61
• /
• 1995

A horizontal starch gal electrophoresis for enzyme proteins extracted from 3 species of Korean planorbid snails; Gyraulus convexiusculus, Hippeutis cantori and Segmentina hemisphaerula was carried out in order to elucidate their genetic relationships.The results from 12 enzymes employed in three different kinds of buffer systems are summarized as follows:1) Two loci from each enzyme of aldehyde oxidase, esterase, glucose phosphate isomerase. isocitrate dehydrogenase, leucine aminopeptidase, malate dehyogenase, peptidase and xanthine oxidase were detected, and only one locus was observed from each of the following four enzymes: 6-phosphogluconate dehydrogenase, glyceraldehyde-phosphate dehydrogenase, glutamate oxaloacetate transaminase and glycerol-3-phosphate dehydrogenase.2) Most of loci in 3 species of planorbid snails employed showed homozygous and monomorphic banding patterns and some of them were specifis as genetic markers among different species. However, a few of loci (EST-1. EST-2 and GPI-2)showed polymorphic banding patterns. 3)Hippeutis cantori and Segmentina hemisphaerula were more closely clustered in a dendrogram with the genetic iddentity value of 0.431, and these two species were lineated with Gyraulus convexiusculus as another cluster at the value of 0.294.In summarizing the above results, three species of Korean planorbid snails employed in this study mostly showed monomorphic enzyme protein banding patterns and genetic differences specific among 3 species.

• Parasites, Hosts and Diseases
• /
• 제38권1호
• /
• pp.45-48
• /
• 2000

An enzyme analysis of the liver fluke, Clonorchis sinensis from Kimhae, Korea and from Shenyang, China was conducted using a horizontal. starch gel electrophoresis in order to elucidate their genetic relationships. A total of eight enzymes was employed from two different kinds of buffer systems. Two loci from each enzyme of aconitase and esterase (${\alpha}-Na{\;}and{\;}{\beta}-Na$) : and only one locus each from six enzymes, gluucose-6-phosphate dehydrogenase (G6PD), ${\alpha}-glycerophosphate$ dehydrogenase (GPD), 3-hydroxybutyrate dehydrogenase (HBDH), malate dehydrogenase (MDH), phosphoglucose isomerase (PGI), and phosphoglucomutase (PGM) were detected. Most of loci in two populations of C. sinensis showed homozygous monomorphic banding patterns and one of them, GPD was specific as genetic markers between two different populations. However, esterase (${\alpha}-Na$), GPD, HBDH and PGI loci showed polymorphic banding patterns. Two populations of C. sinensis were more closely clustered within the range of genetic identity value of 0.998-1.0. In summarizing the above results, two populations of C. sinensis employed in this study showed mostly monomorphic enzyme protein banding patterns, and genetic differences specific between two populations.

• Asian-Australasian Journal of Animal Sciences
• /
• 제22권1호
• /
• pp.1-6
• /
• 2009

Genetic variability is an important component in the ability of populations to adapt in the face of environmental change. Severe human impacts reduced Muzzafarnagri sheep of India from 500,000 in 1972 to 10,989 in 1973-74. Here we report for the first time the effect of this population decline on levels of genetic variability at 13 FAO recommended ovine microsatellite loci and contrast levels of variability to that in a breed from the same geographical region, which differed in numbers, by an order of magnitude (Marwari sheep). Of the 13 loci, 100% were polymorphic in both breeds. A high degree of genetic variation was observed within populations in terms of both allele diversity (number of alleles per locus, >4) and gene diversity (expected heterozygosity, >0.5), which implied that there is still a substantial amount of genetic diversity at the nuclear loci in a declining population. Nevertheless, overall low number of alleles per locus and relatively less abundance of low frequency alleles in Muzzafarnagri sheep suggested that genetic variability has been comparatively reduced in this population. Bottleneck analysis indicated that a genetic bottleneck did not occur during the most recent decline. In addition, we found that the differentiation among populations was moderate ($F_{ST}$= 11.8%). This study on assessment of genetic effects of the population declines in ovines is a step towards identification of genetically impoverished or healthy populations, which could prove to be a useful tool to facilitate conservation planning in this important species of small ruminants.