• 제목/요약/키워드: Allele Frequencies

검색결과 391건 처리시간 0.034초

Allelic Frequencies of 20 Visible Phenotype Variants in the Korean Population

  • Lim, Ji Eun;Oh, Bermseok
    • Genomics & Informatics
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    • 제11권2호
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    • pp.93-96
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    • 2013
  • The prediction of externally visible characteristics from DNA has been studied for forensic genetics over the last few years. Externally visible characteristics include hair, skin, and eye color, height, and facial morphology, which have high heritability. Recent studies using genome-wide association analysis have identified genes and variations that correlate with human visible phenotypes and developed phenotype prediction programs. However, most prediction models were constructed and validated based on genotype and phenotype information on Europeans. Therefore, we need to validate prediction models in diverse ethnic populations. In this study, we selected potentially useful variations for forensic science that are associated with hair and eye color, iris pattern, and facial morphology, based on previous studies, and analyzed their frequencies in 1,920 Koreans. Among 20 single nucleotide polymorphisms (SNPs), 10 SNPs were polymorphic, 6 SNPs were very rare (minor allele frequency < 0.005), and 4 SNPs were monomorphic in the Korean population. Even though the usability of these SNPs should be verified by an association study in Koreans, this study provides 10 potential SNP markers for forensic science for externally visible characteristics in the Korean population.

Prevalence of negative frequency-dependent selection, revealed by incomplete selective sweeps in African populations of Drosophila melanogaster

  • Kim, Yuseob
    • BMB Reports
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    • 제51권1호
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    • pp.1-2
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    • 2018
  • Positive selection on a new beneficial mutation generates a characteristic pattern of DNA sequence polymorphism when it reaches an intermediate allele frequency. On genome sequences of African Drosophila melanogaster, we detected such signatures of selection at 37 candidate loci and identified "sweeping haplotypes (SHs)" that are increasing or have increased rapidly in frequency due to hitchhiking. Based on geographic distribution of SH frequencies, we could infer whether selective sweeps occurred starting from de novo beneficial mutants under simple constant selective pressure. Single SHs were identified at more than half of loci. However, at many other loci, we observed multiple independent SHs, implying soft selective sweeps due to a high beneficial mutation rate or parallel evolution across space. Interestingly, SH frequencies were intermediate across multiple populations at about a quarter of the loci despite relatively low migration rates inferred between African populations. This invokes a certain form of frequency-dependent selection such as heterozygote advantage. At one locus, we observed a complex pattern of multiple independent that was compatible with recurrent frequency-dependent positive selection on new variants. In conclusion, genomic patterns of positive selection are very diverse, with equal contributions of hard and soft sweeps and a surprisingly large proportion of frequency-dependent selection in D. melanogaster populations.

No Association of Cytochrome P450-1B1 Gene Polymorphisms with Risk of Breast Cancer: an Egyptian Study

  • Ibrahim, Mona H;Rashed, Reham A;Hassan, Naglaa M;Al-azhary, Nevin M;Salama, Asmaa I;Mostafa, Marwa N
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권6호
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    • pp.2861-2866
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    • 2016
  • It is thought that population characteristics of breast cancer may be due to a variation in the frequency of different alleles of genes such as CYP1B1. We aimed to determine the association of CYP1B1 polymorphisms in 200 breast cancer cases and 40 controls by PCR-RFLP. Frequencies were assessed with clinical and risk factors in Egyptian patients. The genotype LV and the Leu allele frequencies for patients and controls were 42.9% and 50%, and 52.9% and 53.3%, respectively), with no significant differences observed (P values = 0.8 and 0.6, respectively). There was also no significant association between genotypes and any risk factors for cases (P>0.05) except laterality and metastasis of the tumor (P values=0.006 and 0.06, respectively). The CYP1B1 polymorphism Val432Leu was not associated with breast cancer in Egypt, but may provide clues for future studies into early detection of the disease.

Fusarium Species from Sorghum in Thailand

  • Mohamed Nor, Nik M.I.;Salleh, Baharuddin;Leslie, John F.
    • The Plant Pathology Journal
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    • 제35권4호
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    • pp.301-312
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    • 2019
  • Sorghum is the fifth most important cereal worldwide, spreading from Africa throughout the world. It is particularly important in the semi-arid tropics due to its drought tolerance, and when cultivated in Southeast Asia commonly occurs as a second crop during the dry season. We recovered Fusarium from sorghum in Thailand and found F. proliferatum, F. thapsinum and F. verticillioides most frequently, and intermittent isolates of F. sacchari and F. beomiforme. The relatively high frequencies of F. proliferatum and F. verticillioides, suggest mycotoxin contamination, particularly fumonisins and moniliformin, should be evaluated. Genetic variation within the three commonly recovered species was characterized with vegetative compatibility, mating type, Amplified Fragment Length Polymorphisms (AFLPs), and female fertility. Effective population number ($N_e$) was highest for F. verticillioides and lowest for F. thapsinum with values based on mating type allele frequencies higher than those based on female fertility. Based on AFLP genetic variation, the F. thapsinum populations were the most closely related, the F. verticillioides populations were the most distantly related, and the F. proliferatum populations were in an intermediate position. The genetic variation observed could result if F. thapsinum is introduced primarily with seed, while F. proliferatum and F. verticillioides could arrive with seed or be carried over from previous crops, e.g., rice or maize, which sorghum is following. Confirmation of species transmission patterns is needed to understand the agricultural systems in which sorghum is grown in Southeast Asia, which are quite different from the systems found in Africa, Australia, India and the Americas.

Effects of CYP1A2$^*$1C and CYP1A2$^*$1F Genotypes on the Activity and Inducibility of CYP1A2 Determined by Urinary Caffeine Metabolite Ratio in Koreans

  • Shin, Mi-Kyung;Yi, Hyeon-Gyu;Kwon, Yong-Hyun;Lee, Sung-Keun;Lim, Woo-Sung;Park, Chang-Shin;Kang, Ju-Hee
    • Molecular & Cellular Toxicology
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    • 제3권4호
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    • pp.314-319
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    • 2007
  • The effects of common variants of CYP1A2 gene (CYP1A2$^*$1C and CYP1A2$^*$1F) on the CYP1A2 activity and inducibility were controversial. The aim of the present study is to investigate the effects of CYP1A2$^*$1C and CYP1A2$^*$1F on the activity of CYP1A2 determined by urinary caffeine metabolite ratio in Koreans. As might be expected, there was large inter-individual variation (16-folds) of CYP1A2 activity ranged from 2.41 to 39.58. The mean CYP1A2 activity of smokers was significantly higher than that of non-smokers. The frequencies of CYP1A2$^*$1C (-3858A) and $^*$1F (-164A) alleles were 0.219 and 0.646, respectively. The effect of CYP1A2$^*$1C on the CYP1A2 activity was not significant. However, the CYP1A2 activity of subjects with AA genotype for CYP1A2$^*$1F allele was significantly lower than that of non-AA genotypes (CC, or CA). Interestingly, the significant effect of CYP1A2$^*$1F allele on CYP1A2 activity was not observed in nonsmokers. Our results suggest that CYP1A2$^*$1F allele rather than CYP1A2$^*$1C allele significantly influences on the inducibility of CYP1A2 in Koreans. Owing to small sample size of our study, further studies should be conducted to reveal the inter-ethnic difference or the gene-environmental interaction.

알코올 의존 환자에서의 Aldehyde Dehydrogenase II와 CYP2E1 유전자 다형성과 임상적 특성간의 연관성 (Association of Genetic Polymorphisms of Aldehyde Dehydrogenase II and CYP2E1 and Clinical Characteristics of Patients with Alcohol Dependence)

  • 정인원;김영랑;지경환;김헌
    • 생물정신의학
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    • 제9권1호
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    • pp.42-49
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    • 2002
  • Objective:This study was to explore the relation of genetic polymorphisms of ALDH2 and CYP2E1 to clinical characteristics of alcoholic patients and alcohol induced liver damage. Methods:The genotype and allele frequencies of 128 male hospitalized patients who met DSM-IV criteria for alcohol dependence were compared with 128 healthy male control subjects. The genetic informations of ALDH2 and CYP2E1 were identified with the technique of polymerase chain reaction and restriction fragment length polymorphism. The clinical characteristics of the alcoholic patients were assessed and analyzed in relation to the family history of alcoholism. For the relation of CYP2E1 genetic polymorphism to the liver damage, the blood levels of various liver function indicators such as ALT, AST, and protein were checked out. Results:1) The alcoholic patients with the family history of alcoholism had the earlier onset of age (p=0.001), the longer duration of illness(p=0.045), and higher NCA scores(p=0.018) than those without the family history of alcoholism. 2) Most alcoholic patients were homozygous for $ALDH2^*1$, compared to control subjects.(p=0.000) 3) There was no difference of CYP2E1 distribution between alcoholic patients and control subjects. However, alcoholic patients having mutant c2 allele showed higher alcoholism severity scores(p=0.004) and more hospitalizations(p=0.014) than those having c1 allele. 4) There was no relationship between CYP2E1 genotype and the functional abnormalities of the liver. Conclusion:This study suggests that $ALDH2^*1$ is highly related with alcohol dependence. Also mutant c2 allele of CYP2E1 is correlated with the severity of alcoholism and the number of hospitalization. But genetic polymorphim of CYP2E1 seems to have no relation to liver damages.

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Microsatellite 의 대립유전자 빈도를 이용한 한우의 경제형질과의 연관성 규명 (Potential Allelic Association of Microsatellite Markers on Bovine Chromosome 5 with Carcass Traits in Hanwoo (Korean cattle))

  • 오재돈;공홍식;조병욱;이미랑;전광주;이학교
    • 생명과학회지
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    • 제18권9호
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    • pp.1225-1229
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    • 2008
  • 본 연구는 한우의 5번 염색체 내에 존재하고 있는 10개의 microsatellite marker의 대립유전자 빈도를 이용하여 한우의 경제형질과의 연관성을 지닌 좌위를 탐색하기 위하여 실시하였다. 한우 326두를 대상으로 10개의 유전좌위를 분석한 결과 총 169개의 대립유전자가 검출되었다. 모든 유전좌위에서 다형성이 검출되었으며 각 유전좌위 별 대립유전자의 수는 9에서 28개로 나타났으며 평균 16.9로 나타났다. 가장 높은 PIC 값을 가진 유전좌위는 DIK2400(0.908)이었으며 가장 낮은 유전좌위는 DIK2718 (0.603)으로 검출되었다. 관측된 이형접합도에서는 DIK1048 (0.655)가 가장 높게 나타났으며, DIK2400 (0.906)은 가장 낮은 것으로 검출되었다. 분석된 MS marker들의 대립유전자의 빈도를 이용하여 경제형질과의 연관성을 탐색하기 위하여 각 경제형질별 육종가를 대상으로 상위그룹과 하위그룹으로 나누어 Chi-square검정을 실시하였다. 분석결과 DIK2828의 239 대립유전자는 근내지방도에서 상위그룹과 하위그룹의 빈도차가 유의적인 차이를 보이는 것으로 나타났다. BMC1009의 279 대립유전자는 도체중과 등지방두께에서 유의적인 차이를 확인하였으며 285대립유전자는 도체중, 등지방두께 그리고 근내지방도에서 유의적인 차이가 확인되었다. DIK4329의 200대립유전자는 등심단면적과 등지방두께에서 유의적인 차이가 확인되었다. 본 연구에서 유의적인 차이가 확인된 유전자좌위는 5번 염색체 내 20 (DIK2828), 41 (BMC1009) 그리고 95 (DIK4329) cM로 나타났다.

Association between Polymorphisms of MSTN and MYF5 Genes and Growth Traits in Three Chinese Cattle Breeds

  • Zhang, R.F.;Chen, H.;Lei, C.Z.;Zhang, C.L.;Lan, X.Y.;Zhang, Y.D.;Zhang, H.J.;Bao, B.;Niu, H.;Wang, X.Z.
    • Asian-Australasian Journal of Animal Sciences
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    • 제20권12호
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    • pp.1798-1804
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    • 2007
  • The objective of this study was to assess the association of polymorphisms in MSTN and MYF5 genes with growth traits in three Chinese cattle breeds. Only one homozygous animal with BB genotype at MSTN locus was observed in Jiaxian population which was at Hardy-Weinberg disequilibrium (p<0.05). The frequencies of allele A at MSTN locus and allele B at MYF5 locus in the three Chinese breeds were 0.9550/0.9730/0.9720 and 0.8275/0.7581/0.7523, respectively. Allele A at MSTN locus and allele B at MYF5 locus were dominant in these three populations. No statistically significant differences in growth traits were observed between the genotypes of the Jiaxian breed at MSTN and MYF5 loci and the Nanyang breed at MYF5 locus. However, there were statistically significant differences between the genotypes at MSTN locus of the Nanyang breed for WH, HG, HGI and HGBLR (p<0.05), and of the Qinchuan breed for BLI (p<0.05). The SNP in MYF5 had significant effects on WH and HHC of Qinchuan animals (p<0.05). These results suggest that MSTN and MYF5 are strong candidate genes that influence growth traits in cattle. Other SNPs of MSTN and MYF5 or other linked genes should also be studied, which could lead to the development of selection plans to improve the performance of Chinese cattle and also promote the breeding of genuine beef cattle in China.

TP53 Codon 72 Polymorphisms and Lung Cancer Risk in the Bangladeshi Population

  • Chowdhury, Miraj Kobad;Moniruzzaman, Md;Al Emran, Abdullah;Mostafa, Mohammad Golam;Kuddus, Ruhul H;Uddin, M Aftab
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권8호
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    • pp.3493-3498
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    • 2015
  • Objective: To assess associations between codon 72 polymorphisms (Pro or B and Arg or b alleles) of the TP53 gene and lung cancer risk among Bangladeshis. Materials and Methods: The distribution of the BB, Bb, and bb genotypes and the frequencies of the B and b alleles were determined by PCR-RFLP method using DNA extracted from leucocytes of 50 confirmed lung cancer patients and 50 age-matched controls and the data were analysed. Results: The ratio of BB, Bb, and bb genotypes were in Hardy-Weinberg equilibrium except for the male patients (${\chi}2=4.6$). The B allele is overrepresented among all patients (OR=2.0, p=0.02) and the female patients (OR=4.1, $p{\leq}0.01$) compared to the controls. The BB/bb ratio was also higher among the patients (OR=3.0, p=0.03). The relative risk of cancer for having BB over bb genotype was 1.8 (p=0.04) but no effect was observed for the Bb genotype. The B allele was overrepresented among patients with adenocarcinomas (OR=2.4, $p{\leq}0.01$) and squamous cell carcinomas (OR=2.7, $p{\leq}0.01$) over the controls but the difference was not significant for those with small cell lung carcinomas (OR=1.1, p=0.66). The B allele was overrepresented among patients age 50 or younger (OR=2.7, $p{\leq}0.01$), but not for older patients (OR=1.7, p=0.07), and among smokers compared to the controls (OR=1.8-10.0, $p{\leq}0.01-0.03$). However, no correlation between increasing pack-years and lung cancer was observed. Conclusions: The Pro/Pro (BB) genotype and the B allele are risk factors for lung cancer among Bangladeshis, particularly for people under age 50, women and smokers.

Single Nucleotide Polymorphisms in the Gc Gene for Vitamin D Binding Protein in Common Cancers in Thailand

  • Maneechay, Wanwisa;Boonpipattanapong, Teeranut;Kanngurn, Samornmas;Puttawibul, Puttisak;Geater, Sarayut Lucien;Sangkhathat, Surasak
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권8호
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    • pp.3339-3344
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    • 2015
  • Background: This case-control study aimed to determine if there were any associations between the two single nucleotide polymorphisms (SNPs) in Gc, rs7041 (Asp416Glu) and rs4588 (Thr420Lys) and 3 common cancers (breast, lung and colorectal) in Thai patients. Materials and Methods: Two hundred and eighty two colorectal, 101 breast and 113 lung cancer patients were recruited from one institute during 2011-2013. The controls were age-matched volunteers who had a negative history of index cancers. In addition, vitamin D levels were compared among different genotypes in the 2 SNPs. Results: The minor allele frequencies of rs7041 (G) and rs4588 (A) were 0.32 and 0.24, respectively. Under the dominant model, the study found significant associations between minor-allele genotypes of the SNP rs7041 (TG/GG) and lung cancer (odds ratio [OR] 1.78, 95% CI 1.05-3.03). When subgroup analysis was performed according to sex and age at diagnosis, the study found that the minor-allele genotypes of rs7041 (TG/GG) were significantly associated with colorectal cancer in patients whose age at diagnosis was more than 60 years (OR 1.67, 95%CI 1.06-2.61) and the minor-allele genotypes of rs4588 (CA/AA) were significantly associated with colorectal cancer in males aged 60 years or less (OR 2.34, 95%CI 1.25-4.37). When SNP combinations (rs7041-rs4588) were examined, the TT-CA combination had a significant protective association with lung cancer (OR 0.44, 95% CI 0.22-0.85). On evaluation of serum 25(OH)D levels in 205 individuals without cancer (males 144, females 61), the proportion of subjects with low serum vitamin D (< 20 ng/ml) in those harboring CA or AA genotypes of rs4588 (41.7%) was significantly higher than the CC genotype (15.5%, p-value < 0.01). Conclusions: Genetic polymorphisms in Gc were associated with lung and colorectal cancers in Thai patients. Lower serum 25(OH)D in minor variants of rs4588 may explain this association.