• Asian-Australasian Journal of Animal Sciences
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• 제19권5호
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• pp.617-621
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• 2006

Recently the numbers of the Thai swamp buffalo (Bubalus bubalis), a native species of Thailand, have been rapidly declining, leading to a requirement for conservation programs for this breed. Such studies of the genetic diversity of this species are essential for conservation decisions and to assist the rational implementation of breeding programs. In this study, the genetic diversity of 80 Thai swamp buffalo, randomly selected from seven different research stations of the Thai Department of Livestock Development, were studied using ten cattle microsatellite markers. Polymorphic PCR products were observed at all microsatellite loci, with percentages of polymorphic loci ranging from 80.00 to 100.00%. The population from Payao showed the lowest level of polymorphism. The mean number of alleles per locus was 4.7 with the highest number of alleles being eight (ETH152) and the lowest being three (HAUT27 and ILSTS030). The average unbiased heterozygosity for all seven populations was 0.61 and varied between 0.5314 (Samui) and 0.6798 (Surin). The genetic distance according to NEI's (1972) ranged from 0.0722 to 0.4427. The populations from Surin and Burirum are the closest populations, while populations from Samui and Payao are the most divergent. The information generated by this study will greatly aid in the establishment of effective breeding and conservation programs for the Thai swamp buffalo.

• Asian-Australasian Journal of Animal Sciences
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• 제18권9호
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• pp.1226-1230
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• 2005

The present investigation was undertaken to study the genetic polymorphism of the DRB3 exon 2 in 75 crossbred cattle by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. Five genotypes i.e. HaeIII-a, HaeIII-b, HaeIII-e, HaeIII-ab and HaeIII-ae were observed when the 284 bp PCR products were digested with HaeIII restriction enzyme. The corresponding frequencies of these patterns were 0.53, 0.04, 0.01, 0.38 and 0.04, respectively. Digestion with RsaI restriction enzyme resolved 24 different restriction patterns. The frequencies of these patterns ranged from 0.013 (RsaI-f, RsaI-k and RsaI-c/n) to 0.120 (RsaI-n). The results revealed that the crossbred cows belonged to the RsaI patterns namely b, k, l, a/l, d/s, l/n, l/o and m/n, whose corresponding frequencies were 0.027, 0.013, 0.040, 0.027, 0.040, 0.067, 0.027 and 0.067, respectively. Digestion of the 284 bp PCR product of DRB3.2 gene with PstI in the crossbred cattle did not reveal any restriction site. These results suggested the absence of the recognition site in some of the animals. These results also revealed that the crossbred cows studied were in homozygous as well as heterozygous condition. On the basis of the above results it can be concluded that the DRB3.2 gene was found to be highly polymorphic in the crossbred cattle population.

• Journal of Genetic Medicine
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• 제11권2호
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• pp.69-73
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• 2014

Purpose: Spinocerebellar ataxia (SCA) is a genetically heterogeneous disease for which more than 30 subtypes have been identified. However, 5 subtypes, SCA1, SCA2, SCA3, SCA6, and SCA7, account for more than 60% of cases. In this study, we report the distribution of these 5 subtypes in Korean patients. Materials and Methods: Six hundred and thirty-eight unrelated patients with a presumptive diagnosis of SCA were included in this study. Trinucleotide (CAG) repeat number (TNR) repeat number was determined using fluorescently labeled primers and fragment analysis. Results: A total of 128 unrelated patients (20.1% of all individuals tested) tested positive for SCA subtypes, including SCA1 (5 patients, 3.9% of those testing positive), SCA2 (38 patients, 29.7%), SCA3 (30 patients, 23.4%), SCA6 (39 patients, 30.5%), and SCA7 (16 patients, 12.5%). The mean copy number of pathogenic TNR alleles was $45{\pm}8.5$ for SCA1, $42{\pm}3.1$ for SCA2, $72{\pm}5.4$ for SCA3, $23{\pm}1.5$ for SCA6, and $50{\pm}11.4$ for SCA7. TNR copy number was inversely correlated with onset age in SCA2, SCA6, and SCA7. Conclusion: SCA2, SCA3, and SCA6 are common SCA subtypes in Korean patients and could be screened as a first-line test. Expanded pathogenic allele size was associated with early onset age.

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

• Fisheries and Aquatic Sciences
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• 제15권2호
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• pp.151-155
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• 2012

We used nine microsatellite DNA markers to estimate genetic variation among wild and cultured populations of the sea squirt Halocynthia roretzi. The loci were polymorphic, with 6-32 alleles, and allelic richness ranged from 6.0 to 26.1 in each population. The wild and the cultured populations had similar mean heterozygosities ($H_O$ and $H_E$), allele numbers, and allelic richness. One cultured population with softness syndrome had a lower mean in the observed heterozygosity ($H_O$ = 0.57) and higher mean inbreeding coefficient ($F_{IS}$ = 0.261) than any other populations. This suggests that the loss of genetic variation in the diseased population might be due to increased inbreeding. A neighbor-joining tree and pairwise population estimates of $F_{ST}$ showed moderate genetic differentiation between the wild and the cultured populations. Additionally, the softness syndrome population was genetically divergent from wild populations, but it was genetically close to the cultured populations.

• Animal Systematics, Evolution and Diversity
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• 제39권4호
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• pp.264-271
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• 2023

The edible jellyfish Rhopilema esculentum occurs in waters throughout northeastern Asia, including in Korea, China, and Japan. In Korean waters, R. esculentum has appeared in two regions (Gangwha and Muan). Based on the appearance of young medusae and coastal distribution records, these two regions may be key R. esculentum breeding sites. In the present study, we investigate and compare the genetic structure of R. esculentum in the two regions using mitochondrial sequences (16S ribosomal RNA and cytochrome c oxidase subunit I). The genetic diversity of the R. esculentum population at Ganghwa exceeded that of the population at Muan. Despite considerable geographic separation (400 km) between the two regions(Gangwha and Muan), our haplotype network suggests that the Gangwha and Muan populations of R. esculentum are related. The simple and monotonous genetic structure of the Muan population shows that R. esculentum emergence is relatively recent. In contrast, the Gangwha population shows evolution. Moreover, jellyfish of the Gangwha population are genetically diverse and remain constant despite environmental fluctuations in the Han River. The Gangwha area is considered to be the old origin of R. esculentum in Korea.

• 한국약용작물학회지
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• 제13권5호
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• pp.262-269
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• 2005

The objective of this study was to assess genetic diversity among 6 different wild ginseng populations from New York, Kentucky, North Carolina, Pennsylvania, Tennessee and Virginia, and to compare these wild populations to one cultivated population. RAPD markers were used to estimate the genetic difference among samples from the 7 populations. The 64 random primers were screened, and 15 primers were selected which exhibited the 124 highly reproducible polymorphic markers. The ratio of discordant bands to total bands scored was used to estimate the genetic distance within and among populations. Multidimensional scaling (MDS) of the relation matrix showed distinctive separation between wild and cultivated populations. The MDS result was confirmed using pooled chi-square tests for fragment homogeneity. This study suggests that RAPD markers can be used as population-specific markers for American ginseng.

• 한국정밀공학회지
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• 제16권1호통권94호
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• pp.116-124
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• 1999

In most conventional design optimization of dynamic system, design sensitivities are utilized. However, design sensitivities based optimization method has numbers of drawback. First, computing design sensitivities for dynamic system is mathematically difficult, and almost impossible for many complex problems as well. Second, local optimum is obtained. On the other hand, Genetic Algorithm is the search technique based on the performance of system, not on the design sensitivities. It is the search algorithm based on the mechanics of natural selection and natural genetics. GA search, differing from conventional search techniques, starts with an initial set of random solutions called a population. Each individual in the population is called a chromosome, representing a solution to the problem at hand. The chromosomes evolve through successive iterations, called generations. As the generation is repeated, the fitness values of chromosomes were maximized, and design parameters converge to the optimal. In this study, Genetic Algorithm is applied to the actual dynamic optimization problems, to determine the optimal design parameters of the dynamic system.

• Animal cells and systems
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• 제10권2호
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• pp.65-71
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• 2006

Autosomal Dominant Polycystic Kidney Disease (ADPKD) is one of the most common inherited renal disorders in the world. Mutations in PKD1 located on chromosome 16p13.3 are responsible for 85% of all the ADPKD patients whereas mutations in PKD2 on chromosome 4q21-23 are responsible for the rest of the cases. Genetic heterogeneity and the problems of mutation detection in PKD1 suggest that linkage analysis is an important approach to study the genetics of ADPKD. To evaluate the availability of six (CA)n microsatellite markers for the linkage analysis of ADPKD in the Korean population, we examined the allele frequencies and heterozygosities of the markers. With the exception of KG8, five markers were highly informative, with PIC values over 0.5, but the PIC value of KG8 marker was less informative than other five markers because of the low number of alleles. Therefore, this study will be useful in linkage analysis for ADPKD families in the Korean population.

• Asian-Australasian Journal of Animal Sciences
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• 제23권7호
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• pp.833-847
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• 2010

In the past decade, there have been many advances in whole-genome sequencing in domestic animals, as well as the development of "next-generation" sequencing technologies and high-throughput genotyping platforms. Consequently, these advances have led to the creation of the high-density SNP array as a state-of-the-art tool for genetics and genomics analyses of domestic animals. The emergence and utilization of SNP arrays will have significant impacts not only on the scale, speed, and expense of SNP genotyping, but also on theoretical and applied studies of quantitative genetics, population genetics and molecular evolution. The most promising applications in agriculture could be genome-wide association studies (GWAS) and genomic selection for the improvement of economically important traits. However, some challenges still face these applications, such as incorporating linkage disequilibrium (LD) information from HapMap projects, data storage, and especially appropriate statistical analyses on the high-dimensional, structured genomics data. More efforts are still needed to make better use of the high-density SNP arrays in both academic studies and industrial applications.