• ALGAE
• /
• v.37 no.2
• /
• pp.123-133
• /
• 2022

Genetic diversity and distribution patterns of marine macroalgae are increasingly being documented in Southeast Asia. These studies show that there can be significant levels of genetic diversity and isolation between populations on either side of the Thai-Malay Peninsula. Bostrychia tenellla is a common filamentous red seaweed in the region and the entity is represented by at least two cryptic species. Despite being highly diverse and widespread, genetic variation and population structure of this species complex remains understudied, especially around the Thai-Malay Peninsula. We analyzed genetic diversity and inferred the phylogeographic pattern of specimens identified as B. tenella using the plastid RuBisCo spacer from samples from the Andaman Sea and the Gulf of Thailand. Our genetic analysis confirmed the occurrence of the two cryptic B. tenella species (B and C) along both coasts. Cryptic species B was more common in the area and displayed higher genetic diversity than species C. Historical demographic analyses indicated a stable population for species B, but more recent population expansion for species C. Our analyses also revealed that both cryptic species from the Andaman Sea possessed higher genetic diversity than those of the Gulf of Thailand. We also detected moderate to high levels of gene flow and weak phylogeographic structure of cryptic species B between the two coasts. In contrast, phylogeographic analysis showed genetic differences between populations of both cryptic species within the Andaman Sea. Overall, these results suggest that cryptic B. tenella species around Thai-Malay Peninsula may have undergone different demography histories, and their patterns of genetic diversity and phylogeography were likely caused by geological history and regional sea surface current circulation in the area.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.10 no.2
• /
• pp.79-86
• /
• 2005

Molecular markers have increasingly been used in plant genetic analysis, due to their obvious advantages over conventional phenotypic markers, as they are highly polymorphic, more in number, stable across different developmental stages, neutral to selection and least influenced by environmental factors. Among the PCR based marker techniques, ISSR is one of the simplest and widely used techniques, which involves amplification of DNA segment present at an amplifiable distance in between two identical microsatellite repeat regions oriented in opposite direction. Though ISSR markers are dominant like RAPD, they are more stable and reproducible. Because of these properties ISSR markers have recently been found using extensively for finger printing, pohylogenetic analysis, population structure analysis, varietal/line identification, genetic mapping, marker-assisted selection, etc. In mulberry (Morus spp.), ISSR markers were used for analyzing phylogenetic relationship among cultivated varieties, between tropical and temperate mulberry, for solving the vexed problem of identifying taxonomic positions of genotypes, for identifying markers associated with leaf yield attributing characters. As ISSR markers are one of the cheapest and easiest marker systems with high efficiency in generating polymorphism among closely related varieties, they would play a major role in mulberry genome analysis in the future.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.2
• /
• pp.713-718
• /
• 2015

Background: A number of association studies have been carried out to investigate the relationship between genetic polymorphisms in DNA repair genes and response to radiotherapy-based multimodality treatment of patients with rectal cancer. However, their conclusions were inconsistent. The objective of the present study was to assess the role of DNA repair gene genetic polymorphisms in predicting genetic biomarkers of the response in rectal cancer patients treated with neoadjuvant chemoradiation. Materials and Methods: Studies were retrieved by searching the PubMed database, Cochrane Library, Embase, and ISI Web of Knowledge. We conducted a meta-analysis to evaluate the association between genetic polymorphisms and the response in rectal cancer treated with neoadjuvant chemoradiation by checking odds ratios (ORs) and 95% confidence intervals (CIs). Results: Data were extracted from 5 clinical studies for this meta-analysis. The results showed that XRCC1 RS25487, XRCC1 RS179978, XRCC3 RS861539, ERCC1 RS11615 and ERCC2 RS13181 were not associated with the response in the radiotherapy-based multimodality treatment of patients with rectal cancer (p>0.05). Conclusions: This study shows that DNA repair gene common genetic polymorphisms are not significantly correlated with the radiotherapy-based multimodality treatment in rectal cancer patients.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.2
• /
• pp.513-517
• /
• 2015

Background: Growing evidence suggests that the members of the ubiquitin-proteasome system (UPS) are important for tumorigenesis. HERC4, one component, is a recently identified ubiqutin ligase. However, the expression level and function role of HERC4 in lung cancer remain unknown. Our objective was to investigate any correlation between HERC4 and development of lung cancer and its clinical significance. Materials and Methods: To determine HERC4 expression in lung cancer, an immunohistochemistry analysis of a tissue microarray containing samples of 10 lung normal tissues, 15 pulmonary neuroendocrine carcinomas, 45 squamous epithelial cancers and 50 adenocarcinomas was conducted. Receiver operating characteristic (ROC) curve analysis was applied to obtain a cut-off point of 52.5%, above which the expression of HERC4 was regarded as "positive". Results: On the basis of ROC curve analysis, positive expression of HERC4 was detected in 0/10 (0.0%) of lung normal tissues, in 4/15 (26.7%) of pulmonary neuroendocrine carcinomas, in 13/45 (28.9%) of squamous epithelial cancers and in 19/50 (38.0%) of adenocarcinomas. It showed that lung tumors expressed more HERC4 protein than adjacent normal tissues (${\chi}^2$=4.675, p=0.031). Furthermore, HERC4 positive expression had positive correlation with pT status (${\chi}^2$=44.894, p=0.000), pN status (${\chi}^2$=43.628, p=0.000), histological grade (${\chi}^2$=7.083, p=0.029) and clinical stage (${\chi}^2$=72.484, p=0.000), but not age (${\chi}^2$=0.910, p=0.340). Conclusions: Our analysis suggested that HERC4 is likely to be a diagnostic biomarker for lung cancer.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.7
• /
• pp.2713-2717
• /
• 2015

Background: Possible associations between the single nucleotide polymorphism (SNP) rs8034191 in the aminoglycosidephosphotransferase domain containing 1 (AGPHD1) gene and lung cancer risk have been studied by many researchers but the results have been contradictory. Materials and Methods: A computerized search for publications on rs8034191 and lung cancer risk was performed. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the association between rs8034191 and lung cancer risk with 13 selected case-control studies. Sensitivity analysis, test of heterogeneity, cumulative meta-analysis, and assessment of bias were also performed. Results: A significant association between rs8034191 and lung cancer susceptibility was found using the dominant genetic model (OR=1.344, 95% CI: 1.285-1.406), the additive genetic model (OR=1.613, 95% CI: 1.503-1.730), and the recessive genetic model (OR=1.408, 95% CI: 1.319-1.503). Moreover, an increased lung cancer risk was found with all genetic models after stratification of ethnicity. Conclusions: The association between rs8034191 and lung cancer risk was significant using multiple genetic models, suggesting that rs8034191 is a risk factor for lung cancer. Further functional studies of this polymorphism and lung cancer risk are warranted.

• Journal of Life Science
• /
• v.9 no.6
• /
• pp.671-676
• /
• 1999

RAPD analysis using random primers were tried to evaluate the genetic variation and diversity of the nine garlic cultivars including two foreign varieties. Thirty-two primers out of 70 primers screened were used to amplify genomic DNA of garlic cultivars using polymerase chain reaction(PCR). Among a total of 151 bands amplified by 32 primers, 125 polymorphic bands were subjected to analysis for genetic relationship of garlic cultivars. The estimated size of amplified PCR products were in the range of 932 to 4,060 base pairs. Nine garlic cultivars were classified into two groups, such as group I corresponded to Changnyung and Hungary cultivars, and group II, Namdo, Sandong from China, Yecheon, Euiseong, Youngweol, Danyang, Jeongsun cultivars, with the genetic distance value of 0.271. The major ecological types of garlics, so called southern and northern types, was grouped in the genetic distance value of 0.200. The results presented in this study suggest that RAPD analysis are likely to be useful for identification of cultivars and evaluation of genetic origin in garlics.

• Biomedical Science Letters
• /
• v.24 no.3
• /
• pp.221-229
• /
• 2018

Trichophyton rubrum is one of the well-known pathogenic fungi and causes dermatophytosis and cutaneous mycosis in human world widely. However, there are not an available sequence type (ST) classification methods and previous studies for T. rubrum until now. Therefore, currently, molecular biological tools using their DNA sequences are used for genotype identification and classification. In the present study, in order to characterize the genetic diversity and the phylogenetic relation of T. rubrum clinical isolates, five different housekeeping genes, such as actin (ACT), calmodulin (CAL), RNA polymerase II (RPB2), superoxide dismutase 2 (SOD2), and ${\beta}$-tubulin (BT2) were analyzed using by multilocus sequence typing (MLST). Also, DNA sequence analysis was performed to examine the differences between the sequences of Trichophyton strains and the identified genetic variations sequence. As a result, most of the sequences were shown to have highly matched rates in their housekeeping genes. However, genetic variations were found on three different positions of ${\beta}$-tubulin gene and were shown to have changed from $C{\rightarrow}G$ (1766), $G{\rightarrow}T$ (1876), and $C{\rightarrow}A$ (1886). To confirm the association with T. rubrum inheritance, a phylogenetic tree analysis was performed. It was classified as four clusters, but there was little significant correlation. Even so, MLST analysis is believed to be helpful for determining the genetic variations of T. rubrum in cases where there is more large-scale data accumulation. In conclusion, the present study demonstrated the first MLST analysis of T. rubrum in Korea and explored the possibility that MLST could be a useful tool for studying the epidemiology and evolution of T. rubrum through further studies.

• Korean Journal of Plant Resources
• /
• v.17 no.3
• /
• pp.265-271
• /
• 2004

Genetic variation is the basis of crop improvement. Limited genetic diversity in a crop species may restrict the amount of genetic improvement that can be achieved through plant breeding. Soybean is one of the world's most important crops. A potential source of genetic variability for the cultivated soybean is the wild species G. soja Sieb. ＆amp; Zucc. Amplified fragment length polymorphism (AFLP) analysis is a PCR-based technique, which can detect a 10-fold greater nubmer of loci than other DNA marker analysis. Twenty cultivated soybeans and two-hundred wild soybeans were used to determine genetic vatiations by AFLPs and evaluate the usefulness of AFLPs as DNA markers. Six-hundred and ten fragments were detected with an average of 56 AFLP fragments produced per primer in a total of 11 AFLP primer pairs. The number of polymorphic loci detected per primer ranged from 7 to 20 and the polymorphism was greater in wild than in cultivated soybean. F$_2$ segregation analysis of four AFLP fragments in combination of Hwaeomputkong ${\times}$ PI 417479 indicated that they segregate as stable Mendelian loci with 3 : 1. This results strongly suggest that the AFLP analysis is a good technique for the detection of genetic polymorphism in a wide plant species.

• Journal of Mushroom
• /
• v.18 no.4
• /
• pp.323-330
• /
• 2020

Agaricus bisporus is an important edible mushroom that is used as a functional food. In this study, European A. bisporus strains were analyzed for genetic diversity, population structure, and genetic differentiation using simple sequence repeat (SSR) markers. European A. bisporus strains were divided into four groups by distance-based analysis and two subpopulations by model-based analysis. The SSR markers used in this study did not group European A. bisporus strains by geographical region or pileus color. Genetic diversity was high in Group 4 based on distance-based analysis and Pop. 2 based on model-based analysis. A. bisporus strains showed very low genetic differentiation. The results of this study can be used for breeding A. bisporus in the future.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.55 no.5
• /
• pp.742-750
• /
• 2022

This study aimed to monitor the distribution of Cobitidae in Korea by the identification of species using genetic analysis. Based on the genetic analysis, Cobitidae species in four of five domestic fish farms consisted of only Chinese muddy loach Misgurnus mizolepis, but muddy loach Misgurnus anguillicaudatus was also present it in one fish farm. In the case of imported Cobitidae species, in addition to Chinese muddy loach and muddy loach, the harmful species Paramisgurnus dabryanus, was also present. Chinese muddy loach accounted for 20%, 67%, and 60% of the S6, S7, and S8 samples, respectively. An analysis of the total length, body length, and weight showed that domestic Chinese muddy loach showed higher values than imported muddy loach, and imported Chinese muddy loach showed similar values to P. dabryanus. There were no significant differences in the country of origin of the three species. Thus, the mitochondrial cytochrome c oxidase subunit I gene sequence was analyzed and compared the verification of species identification. The three species of Cobitidae were genetically divided into three groups and determined to have genetic differences. These results indicate that it is necessary to reduce the heterogeneous mixing rate through discriminating species by genetic analysis.