• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.2033-2036
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• 2013

Many studies have suggested that the XRCC1 Arg280His gene polymorphism might be involved in the development of hepatocellular carcinoma (HCC). However, the results have been inconsistent. In this study, the authors performed a meta-analysis to assess the association between XRCC1 Arg280His and HCC susceptibility. Published literature from PubMed, EMBASE and CNKI Data was searched. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using fixed- or random-effects models when appropriate. Begg's test was used to measure publication bias. A total of 7 case-control studies covering 1,448 HCC cases and 1,544 controls were included. No significant variation in HCC risk was detected in any of the genetic models overall. In the stratified analysis, four studies with sample sizes over 300 produced similar results. The corresponding pooled ORs were not substantially altered after the exclusion of three studies deviating from Hardy-Weinberg equilibrium in the control group, which indicated reliability for our meta-analysis results.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.461-465
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• 2002

Nine microsatellite loci were analyzed in 84 random individuals to characterize the genetic variability of three domestic goat breeds found in Korea and China: Korean goat, Chinese goat and Saanen. Allele diversity, heterozygosity, polymorphism information content, F-statistics, indirect estimates of gene flow (Nm) and Nei's standard distances were calculated. Based on the expected mean heterozygosity, the lowest genetic diversity was exhibited in Korean goat ($H_E$=0.381), and the highest in Chinese goat ($H_E$=0.669). After corrections for multiple significance tests, deviations from Hardy-Weinberg equilibrium were statistically significant over all populations and loci, reflecting the deficiencies of heterozygotes (global $F_{IS}$=0.053). Based on pairwise FST and Nm between different breeds, there was a great genetic differentiation between Korean goat and the other two breeds, indicating that these breeds have been genetically subdivided. Similarly, individual clustering based on the proportion of shared alleles showed that Korean goat individuals formed a single cluster separated from the other two goat breeds.

• Genomics & Informatics
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• v.6 no.1
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• pp.14-17
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• 2008

GENDISCAN study (Gene Discovery for Complex traits in Asian population of Northeast area) was designed to incorporate methodologies which enhance the power to identify genetic variations underlying complex disorders. Use of population isolates as the target population is a unique feather of this study. However, population isolates may have hidden inbreeding structures which can affect the validity of the study. To understand how this issue may affect results of GENDISCAN, we estimated inbreeding coefficients in two study populations in Mongolia. We analyzed the status of Hardy-Weinberg Equilibrium (HWE), polymorphism information contents (PIC), heterozygosity, allelic diversity, and inbreeding coefficients, using 317 and 1,044 STR (short tandem repeat) markers in Orkhontuul and Dashbalbar populations. HWE assumptions were generally met in most markers (88.6% and 94.2% respectively), and single marker PIC ranged between 0.2 and 0.9. Inbreeding coefficients were estimated to be 0.0023 and 0.0021, which are small enough to assure that conventional genetic analysis would work without any specific modification. We concluded that the population isolates used in GENDISCAN study would not present significant inflation of type I errors from inbreeding effects in its gene discovery analysis.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.5
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• pp.483-493
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• 1996

Advances in silage technology, including precision chop forage harvesters, improved silos, polyethylene sheeting, shear cutting silo unloaders, and the introduction of total mixed rations, have made silage the principal method of forage preservation. A better understanding of the biochemistry and microbiology of the four phases of the ensiling process has also led to the development of numerous silage additives. Although acids and acid salts still are used to ensile low-DM forages in wet climates, bacterial inoculants have become the most widely used silage additives in the past decade. Commercial inoculants can assure a rapid and efficient fermentation phase; however, in the future, these products also must contribute to other areas of silage management, including the inhibition of enterobacteria, clostridia, and yeasts and molds. Nonprotein nitrogen additives have the problems of handling, application, and reduced preservation efficiency, which have limited their wide spread use. Aerobic deterioration in the feedout phase continues to be a serious problem, especially in high-DM silages. The introduction of competitive strains of propionic acid-producing bacteria, which could assure aerobically stable silages, would improve most commercial additives. New technologies are needed that would allow the farmer to assess the chemical and microbial status of the silage crop on a given day and then use the appropriate additive(s).

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.1
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• pp.1-5
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• 2008

To analyze genetic effects on milk production traits, 164 unrelated Italian Jersey cows reared in 15 farms located in Southern Italy were characterized at the growth hormone locus. Using a Polymerase Chain Reaction-Restriction Fragment Length Polymorphism protocol all three possible genotypes for the Leucine/Valine polymorphism were identified even if in the considered population the number of homozygous animals (Leucine/Leucine = 36; Valine/Valine = 28) was smaller than Leucine/Valine (n = 100) cows; the Hardy-Weinberg equilibrium was verified. Statistical analysis showed that daily milk yield in the Leucine/Leucine genotype was higher (p<0.01) than in Leucine/Valine (22.76 kg vs. 16.96 kg ); cows with Leucine/Valine genotype differed significantly from Leucine/Leucine and Valine/Valine genotypes particularly in fat (4.95% vs. 4.13% and 4.82%, respectively) and protein content (4.00% vs. 3.47% and 3.79%, respectively). No significant effect on lactation length was observed.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.763-767
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• 2014

Aim: To study the contribution of genetic variation in RAD51 to risk of esophageal squamous cell carcinoma (ESCC). Methods: Three single nucleotide polymorphisms (SNPs) in RAD51 (rs1801320, rs4144242 and rs4417527) were genotyped in 316 ESCC patients and 316 healthy controls in Anyang area of China using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). Demographic variables between cases and controls were statistically compared by T test and Chi-square test. Hardy-Weinberg equilibrium was evaluated by the Chi-square test. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to measure any association with ESCC. Haplotype frequencies were estimated by Phase 2.1. Result: The genotype frequencies of rs1801320, rs4144242 and rs4417527 in patients with ESCC demonstrated no significant differences from those in control group (P>0.05). When the haplotypes of these three SNPs were constructed and their relationships with ESCC risk investigated, however, CGG was observed to increase the risk (P=0.020, OR=2.289). Conclusions: There was no association between the three SNPs of RAD51 and ESCC susceptibility in our Chinese population. However, the CGG haplotype might be a risk factor.

• Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.303-309
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• 2013

Microsatellite markers are important for gene mapping and for marker-assisted selection. Sixty-five polymorphic microsatellite markers were developed with an enriched partial genomic library from olive flounder Paralichthys olivaceus an important commercial fish species in Korea. The variability of these markers was tested in 30 individuals collected from the East Sea (Korea). The number of alleles for each locus ranged from 2 to 33 (mean, 17.1). Observed and expected heterozygosity as well as polymorphism information content varied from 0.313 to 1.000 (mean, 0.788), from 0.323 to 0.977 (mean, 0.820), and from 0.277 to 0.960 (mean, 0.787), respectively. Nine loci showed significant deviation from the Hardy-Weinberg equilibrium after sequential Bonferroni correction. Analysis with MICROCHECKER suggested the presence of null alleles at five of these loci with estimated null allele frequencies of 0.126-0.285. These new microsatellite markers from genomic libraries will be useful for constructing a P. olivaceus linkage map.

• Journal of Plant Biology
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• v.38 no.4
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• pp.329-336
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• 1995

Raphanus sativus L. var. hortensis f. raphanistroides (wild radish: Brassicaceae), a herbaceous perennial, occurs only on beaches in East Asia. Genetic diversity and population structure of seven Korean populations were investigated using starch gel electrophoresis. Although the Korean populatins are small, isolated with patchy distribution, the population maintain a moderate level of genetic diversity; the mean percentage fo polymorphic loci was 51.4%, mean number of alleles per locus was 1.84, and mean expected heterozygosity was 0.116. A combination of animal-outcrossing breeding system, wide geographical distribution, restricted ecological distribution, and a propensity for high fecundity may in part be explanatory factors contributing the moderate level of genetic diversity within populations. An overall excess of homozygotes relative to Hardy-Weinberg expetations (mean FISa=0.116) indicates that consanguineous mating occur within wild radish populations, leading to a family structure within a circumscribed area. Although population of wild radish experience a limited gene flow, only 5% of the total genetic variation found in Korean wild radish populations examined is due to differences among populations (mean GST=0.052). This value is considerably lower than the mean values of species with similar life history and ecological characteristics. However, significant differences were found in allele frequencies between populations for all polymorphic loci (P<0.01). It is supposed that directional selection toward genetic uniformity (similar gene frequencies) in a relatively homogenous habitat is thought to be operated among Korean wild radish populations.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.227-233
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• 2001

Four polymorphic allozymes were used for genetic analysis of overwintering populations of field diamondback moth, Plutella xylostella (Linne). Different allele frequencies were found among three local populations of Andong, Youngchon, and Yangsan in all loci. Two allozyme loci (acid phosphatase and phosphoglucomutase) showed significant deviation from Hardy-Weinberg equilibrium in allele frequencies among these populations. Estimated Nei's genetic distance varied from 0.0151 between Yangsan and Youngchon to 0.0877 between Andong and Youngchon. Compared with the previous genetic distances in this moth, a little higher genetic differentiation among these overwintering populations suggests that there would be a specific genetic bottleneck in each local population during overwintering period.

• Animal cells and systems
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• v.4 no.1
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• pp.87-90
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• 2000

Essential hypertension is a multifactorial disease, and has been shown to be associated with insulin resistance. The relationship between the genetic variation of the insulin receptor (INSR) gene and essential hypertension In Korean population was investigated by the Nsi 1 restriction fragment length polymorphism (RFLP) pattern of this gene. The observed genotype frequencies of INSR gene were not deviated from those expected for the Hardy-Weinberg equilibrium (HWE), but a significant association was observed between essential hypertension and N1 allele of Nsi 1 RFLP at the INSR gene ($X^2$-test; P<0.05). Moreover, the frequency of N1 allele was significantly different between normotensives and essential hypertensives in subgroups that were not obese ($X^2$-test; P<0.05). These data suggest that the Nsil RFLP of INSR gene may be a useful genetic marker for essential hypertension in Korean population.