• 제목/요약/키워드: genetic association studies

검색결과 617건 처리시간 0.028초

Brain-Derived Neurotrophic Factor Val66Met 다형성과 정신분열병의 관련 연구 (An Association Study of the Brain-Derived Neurotrophic Factor Val66Met Gene Polymorphism and Schizophrenia)

  • 이화영;김대진;김용구
    • 생물정신의학
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    • 제13권4호
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    • pp.267-272
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    • 2006
  • Objectives : Schizophrenia is a clinically heterogenous disease with a strong genetic component. Many studies have suggested that brain-derived neurotrophic factor(BDNF) is involved in the pathophysiology of schizophrenia. This study was performed to determine whether there is an association between BDNF Val66Met polymorphism and schizophrenia. Methods : To identify any genetic predisposition to schizophrenia, we investigated the BDNF Val66Met polymorphism in 106 patients with schizophrenia and 147 normal controls with PCR-RFLP method. Statistical analyses were used to test the association between and BDNF Val66Met genotype and Schizophrenia. Results : No association was found between BDNF Val66Met polymorphism and schizophrenia. No significant differences were found comparing the BDNF genotype distributions according to the age of onset, the number of admission and familial loading in schizophrenia. Conclusion : This result indicates that BDNF Val66Met polymorphism is not associated with schizophrenia. However, further studies with a large number of subjects are needed to confirm whether the BDNF gene is related to schizophrenia.

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배나무(Pyrus spp.) 유전체 연구 현황 (Researches of pear tree (Pyrus spp.) genomics)

  • 오영재;신현석;김금선;한현대;김윤경;김대일
    • Journal of Plant Biotechnology
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    • 제42권4호
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    • pp.290-297
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    • 2015
  • 배나무는 원산지와 분화방향에 따라 유럽, 미국, 호주 등에서 주로 재배되는 서양배와 중국, 일본, 한국 등 동남 아시아 지역을 중심으로 분포 및 재배되고 있는 동양배로 구분된다. 17개의 기본염색체를 가진 배나무는 대부분 이배성(2n=2x=34)이며, 단일 S 유전자좌에 의해 조절되는 자가불화합성과 과수 작물의 주요 특징인 유년성으로 인해 유전 연구 및 정밀한 품종 육성에 큰 제한을 받고 있다. 배나무속 식물의 유전연구는 분자생물학 관련 기술의 발달로 다양한 형태의 분자 표지의 개발이 이루어짐과 동시에 유연관계분석, 유전자지도작성, QTL 분석과 같은 다양한 유전연구에 활발히 이용되었다. 또한 배나무의 유전자지도는 병 저항성이나 다양한 유용형질과 연관된 QTL 확인을 위한 연구로 이어지고 있다. 대량 병렬 반응 및 다중처리를 토대로 획기적인 염기서열 분석 비용의 감소를 이뤄낸 NGS 기술은 대용량, 고효율, 저비용으로 식물 유전체 해독을 가능하게 하여, 중국배 'Danshansuli'와 유럽배 'Bartlett'에서 유전체 분석이 완료되었다. 최근 국내에서는 황금배, 청실리 및 미니배의 resequencing 및 GBS를 통한 SNP 탐색 등의 연구를 통해 화기, 숙기 당도 등 농업적으로 유용형질에 대한 게놈전체 연관분석을 수행하고 있다.

Genetic Variations of Trichophyton rubrum Clinical Isolates from Korea

  • Yoon, Nam-Sup;Kim, Hyunjung;Park, Sung-Bae;Park, Min;Kim, Sunghyun;Kim, Young-Kwon
    • 대한의생명과학회지
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    • 제24권3호
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    • pp.221-229
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    • 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.

Methylenetetrahydrofolate Reductase C677T Polymorphism and Cervical Cancer Risk: a Meta-Analysis

  • Guo, Li-Na
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권5호
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    • pp.2193-2197
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    • 2012
  • Background: Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in the metabolism of folate, and the role of MTHFR C677T polymorphism in cervical carcinogenesis is still controversial. Method: We performed a meta-analysis of all relevant case-control studies that examined any association between the C677T polymorphism and cervical cancer risk. We estimated summary odds ratios (ORs) with their confidence intervals (CIs) to assess links. Results: Finally, 10 studies with a total of 2113 cervical cancer cases and 2804 controls were included. Results from this meta-analysis showed that significantly elevated cervical cancer risk was associated with the MTHFR T allele in the Asian population under conditions of two genetic comparison models (for TT vs. CC, OR = 1.37, 95%CI 1.00-1.87, P = 0.050; for TT vs. TC+CC: OR = 1.34, 95%CI 1.01-1.77, P = 0.039). However, there was no obvious association between the MTHFR C677T polymorphism and cervical cancer risk in the other populations. Conclusion: The MTHFR C677T polymorphism is associated with cervical cancer risk in Asians, while any possible link in the Caucasian population needs further studies.

Highly Polymorphic Bovine Leptin Gene

  • Yoon, D.H.;Cho, B.H.;Park, B.L.;Choi, Y.H.;Cheong, H.S.;Lee, H.K.;Chung, E.R.;Cheong, I.C.;Shin, H.D.
    • Asian-Australasian Journal of Animal Sciences
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    • 제18권11호
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    • pp.1548-1551
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    • 2005
  • The leptin, an anti-obesity protein, is a hormone protein expressed and secreted mainly from adipocyte tissue, and involved in regulation of body weight, food intake and energy metabolism. In an effort to discover polymorphism(s) in genes whose variant(s) might be implicated in phenotypic traits of growth, we have sequenced exons and their boundaries of leptin gene including 1,000 bp upstream of promoter region with twenty-four unrelated Korean cattle. Fifty-seven sequence variants were identified: fourteen in 5' flanking region, twenty-seven in introns, eight in exons, and eight in 3' flanking region. By pair-wise linkage analysis among polymorphisms, ten sets of SNPs were in absolute linkage disequilibrium (LD) (|D'| = 1 and $r^2$ = 1). Among variants identified, thirty-six SNPs were newly identified, and twenty-one SNPs, which were reported in other breeds, were also confirmed in Korean cattle. The allele frequencies of variants were quite different among breeds. The information from SNPs of bovine leptin gene could be useful for further genetic studies of this gene.

E-Selectin S128R Polymorphism is Associated with Cancer Risk: a Meta-analysis

  • Cheng, Da-Ye;Hao, Yi-Wen;Zhou, Wen-Ling;Ma, Yi-Ran
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권7호
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    • pp.3247-3252
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    • 2014
  • Background: Genetic factors have been shown to play an important role in the development of cancers. However, individual studies may fail to completely demonstrate complicated genetic relationships because of small sample size. Therefore, we performed a meta-analysis to evaluate the association of E-selectin Ser128Arg (S128R) with cancer risk. Materials and Methods: A literature search in PubMed, Embase, Web of Science, Science Direct, SpringerLink, EBSCO, Wanfang, and Chinese National Knowledge Infrastructure databases was carried out to identify studies of the association between E-selectin S128R polymorphism and cancer risk. The odds ratio (OR) with 95% confidence intervals (95%CIs) were used to assess the strength of association. Results: A total of eight studies involving 1,675 cancer cases and 2,285 controls were included in the meta-analysis. In overall populations, S128R polymorphism seemed to be associated with cancer risk (Arg allele vs Ser allele: OR=1.65, 95%CI =1.33-2.04, p<0.01; Arg/Arg+Arg/Ser vs Ser/Ser: OR=1.87, 95%CI =1.48-2.36, p<0.01; Arg/Ser vs Ser/Ser: OR=1.80, 95%CI =1.51-2.14, p<0.01). Similarly, subgroup analysis by ethnicity and source of control also revealed that this polymorphism was related to cancer risk. Conclusions: Our meta-analysis revealed that there was association between the E-selectin S128R polymorphism and the risk of cancer. Further large and well-designed studies are needed to confirm this association.

형제 자료에 근거한 유전연관성 추세 검정법의 비교 (Comparison of Trend Tests for Genetic Association with Sibship Data)

  • 오영신;김한상;송혜향
    • 응용통계연구
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    • 제23권5호
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    • pp.845-855
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    • 2010
  • 의학의 여러 분야의 연관성 연구에서 효율성이 높은 방법으로 채택되고 있는 질병-대조 연구계획을 다수 형제 자료에 근거한 유전연관성 연구에 적용하기 위해서는 가족 자료에 근거한 추세 검정통계량이 요구된다. 독립된 개체에 적용하는 Cochran-Armitage 추세 검정통계량은 가족 자료의 경우 제 1종 오류가 보장되지 않으며, 동일 가족의 다수 형제 자료로 인한 공분산을 감안한 추세 검정통계량이 제시되어야 한다. 본 논문에서는 특히 동일 가족의 질병형제수에 따른 가중을 도입하여 질병과 관련된 마커좌위에서의 유전자형 자료가 수집되는 경우에 검정력이 더욱 높게 되는 검정통계량을 제안한다. 예제 가족 자료로 가중을 고려한 경우와 고려하지 않은 경우의 검정통계량을 계산하여 비교한다.

Application of Random Forests to Association Studies Using Mitochondrial Single Nucleotide Polymorphisms

  • Kim, Yoon-Hee;Kim, Ho
    • Genomics & Informatics
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    • 제5권4호
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    • pp.168-173
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    • 2007
  • In previous nuclear genomic association studies, Random Forests (RF), one of several up-to-date machine learning methods, has been used successfully to generate evidence of association of genetic polymorphisms with diseases or other phenotypes. Compared with traditional statistical analytic methods, such as chi-square tests or logistic regression models, the RF method has advantages in handling large numbers of predictor variables and examining gene-gene interactions without a specific model. Here, we applied the RF method to find the association between mitochondrial single nucleotide polymorphisms (mtSNPs) and diabetes risk. The results from a chi-square test validated the usage of RF for association studies using mtDNA. Indexes of important variables such as the Gini index and mean decrease in accuracy index performed well compared with chi-square tests in favor of finding mtSNPs associated with a real disease example, type 2 diabetes.

The AURKA Gene rs2273535 Polymorphism Contributes to Breast Carcinoma Risk - Meta-analysis of Eleven Studies

  • Guo, Xu-Guang;Zheng, Lei;Feng, Wei-Bo;Xia, Yong
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권16호
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    • pp.6709-6714
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    • 2014
  • The rs2273535 polymorphism in the AURKA gene had proven to be associated with breast carcinoma susceptibility. Nevertheless, the results of different studies remain contradictory. A meta-analysis covering 28, 789 subjects from eleven different studies was here carried out in order to investigate the association in detail. The random effects model was used to analyze the pooled odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs). A significant relationship between the rs2273535 polymorphism and breast tumors was found in an allelic genetic model (OR: 1.076, 95% CI: 1.004-1.153, p=0.040, $P_{heterogeneity}$=0.002). No significant association was detected in a homozygote model (OR: 1.186, 95% CI: 0.990-1.423, P=0.065, $P_{heterogeneity}$=0.002), a heterozygote model (OR: 1.016, 95% CI: 0.959-1.076, p=0.064, $P_{heterogeneity}$=0.000), a dominant genetic model (OR: 1.147, 95% CI: 0.992-1.325, p=0.217, $P_{heterogeneity}$=0.294) and a recessive genetic model (OR: 1.093, 95% CI: 0.878-1.361, p=0.425, $P_{heterogeneity}$=0.707). A significant relationship between the rs2273535 polymorphism in the AURKA gene and breast tumor in Asian group was found in an allelic genetic model (OR: 1.124, 95% CI: 1.003-1.29, p=0.044, $P_{heterogeneity}$=0.034), a homozygote model (OR: 1.229, 95% CI: 1.038-1.455, p=0.016, $P_{heterogeneity}$=0.266) and a recessive genetic model (OR: 1.227, 95% CI: 1.001-1.504, p=0.049, $P_{heterogeneity}$=0.006). A significant association was thus observed between the rs2273535 polymorphism in the AURKA gene and breast cancer risk. Individuals with the rs2273535 polymorphism in the AURKA gene have a higher risk of breast cancer in Asian populations, but not in Caucasians.

XRCC1 Gene Polymorphisms and Breast Cancer Risk: A Systematic Review and Meta-analysis Study

  • Moghaddam, Ali Sanjari;Nazarzadeh, Milad;Moghaddam, Hossein Sanjari;Bidel, Zeinab;Karamatinia, Aliasghar;Darvish, Hossein;Jarrahi, Alireza Mosavi
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권sup3호
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    • pp.323-335
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    • 2016
  • Breast cancer risk assessment has developed during years and evaluation of genetic factor affecting risk of breast cancer is an important component of this risk assessment. The aim of this meta-analysis was to investigate the role of XRCC1 polymorphisms (Arg194Trp, Arg280His and Arg399Gln) in risk of breast cancer among different population and categories of menopausal status.PubMed, Medline, Web of Science, and PubMed Central were systematically searched to identify studies evaluating association between breast cancer and XRCC1 gene polymorphisms (Arg194Trp, Arg280His and Arg399Gln). Two authors independently extracted required information. Odds Ratios were pooled for four genetic inheritance models using both fixed and the DerSimonian and Laird random-effect models. Egger's test and contour-enhanced funnel plot was used to evaluate publication bias and small study effect. Additional subgroup analysis was performed for menopausal status, ethnicity, and source of controls. After evaluation and applying inclusion criteria on extracted studies, fifty three studies were included in this meta-analysis. For polymorphisms of Arg194Trp and Arg280His, no significant association was observed in all genetic models. Arg194Trp had a protective effect in post-menopausal status only in homozygote model (OR=0.57 [0.37-0.88]). Arg399Gln showed significant association with breast cancer in homozygote (OR=1.21 [1.10-1.34]), dominant (OR=1.09 [1.03-1.15]) and recessive (OR=1.21 [1.09- 1.35]) genetic models. Arg399Gln was associated with higher risk in post-menopausal status for homozygote and heterozygote models. Our findings suggest that XRCC1 gene polymorphisms modify breast cancer risk in different populations and different categories of menopausal status.