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41.
Interleukin-6 (IL-6) may play an important role in the pathogenesis of Graves' ophthalmopathy (GO). The aim of this study was to analyze the association of IL-6 gene promoter polymorphism, at position -174 (G→C, termed as G-174C), which may affect IL-6 production, with the development of GO. The G-174C polymorphism was determined in 279 Polish-Caucasian patients with Graves' disease (GD), of which 108 had clinically evident ophthalmopathy (NOSPECS class III or higher) and 186 healthy Polish adults. In patients with GD, the frequencies of the C allele (45 vs 42%; P=0.35) and C/C genotype (20 vs 15%; P=0.13) were not significantly different compared to controls. Subdividing patients with GD for the presence of eye disease revealed that the C allele (44 vs 45%; P=0.76) and C/C genotype (20 vs 20%; P=0.92) were equally distributed in patients with or without ophthalmopathy. There was also no association between the G-174C polymorphism and the severity of eye changes. Finally, IL-6 genotypes were not associated with laboratory findings (thyroid volume, serum IL-6 and thyroid autoantibodies levels) in patients with GD at diagnosis. Our results suggest that G-174C polymorphism of the IL-6 gene does not contribute to the development and severity of GO.  相似文献   
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A survey of the genetic ancestry of 125 Cambodian children resident in Siem Reap province was undertaken, based on eight Y-chromosome binary polymorphisms and sequencing of the mtDNA HV1 region. The data indicated a largely East Asian paternal ancestry and a local Southeast Asian maternal ancestry. The presence of Y-chromosomes P* and R1a1* was suggestive of a small but significant Indo-European male ancestral component, which probably reflects the history of Indian, and later European, influences on Cambodia.  相似文献   
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Multiple-allele single nucleotide polymorphisms (SNPs) are potentially useful for forensic DNA analysis as they can provide more discrimination power than normal binary SNPs. In addition, the presence in a profile of more than two alleles per marker provides a clearer indication of mixed DNA than assessments of imbalanced signals in the peak pairs of binary SNPs. Using the 1000 Genomes Phase III human variant data release of 2014 as the starting point, this study collated 961 tetra-allelic SNPs that pass minimum sequence quality thresholds and where four separate nucleotide substitution alleles were detected. Although most of these loci had three of the four alleles in combined frequencies of 2% or less, 160 had high heterozygosities with 50 exceeding those of ‘ideal’ 0.5:0.5 binary SNPs. From this set of most polymorphic tetra-allelic SNPs, we identified markers most informative for forensic purposes and explored these loci in detail. Subsets of the most polymorphic tetra-allelic SNPs will make useful additions to current panels of forensic identification SNPs and ancestry-informative SNPs. The 24 most discriminatory tetra-allelic SNPs were estimated to detect more than two alleles in at least one marker per profile in 99.9% of mixtures of African contributors. In European contributor mixtures 99.4% of profiles would show multiple allele patterns, but this drops to 92.6% of East Asian contributor mixtures due to reduced levels of polymorphism for the 24 SNPs in this population group.  相似文献   
44.

Purpose

Sensitization to house dust mite (Dermatophagoides pteronyssinus) is a considerable risk factor for the progression of allergic disease. The group 2 allergen from Dermatophagoides pteronyssinus, Der p 2, is considered a major one in patients with specific immunoglobulin E (IgE) to Der p 2. Der p 2 has structural homology with myeloid differentiation 2 (MD-2), which is involved in the lipopolysaccharide-binding component of the Toll-like receptor 4 signaling pathway and the development of inflammation. The aim of this study was to examine the genetic association of single nucleotide polymorphisms (SNPs) in the promoter region of MD-2 with Der p 2-sensitive allergy.

Methods

We investigated associations between cohort''s characteristics, including 280 allergic and 80 healthy subjects by examining total IgE, eosinophils, D. pteronyssinus-specific IgE, Der p 2-specific IgE, the number of IgE-producing B cells induced by Der p 2, and the odds ratio of allergic symptoms.

Results

Based on the 1,000 genome project data, the minor allele frequencies of the rs1809441 and rs1809442 are 0.467 and 0.474, respectively. However, the correlation of linkage disequilibrium (LD) between these 2 SNPs is D''=1, the genotype frequencies of the 2 MD-2 (LY96) SNPs (rs1809441 and rs1809442) that are located nearby were significantly different between allergic and health subjects: the TT genotype of rs1809441 and the GG genotype of rs1809442 were more frequent in allergic subjects than in healthy subjects (16.1% vs 2.5% in both genotypes). The allergic patients with these genotypes exhibited significantly higher levels of D. pteronyssinus-specific IgE and Der p 2-specific Ig E, and a larger number of Der p 2-activated B cells. In addition, these 2 SNPs in the MD-2 promoter region were significantly associated with the prevalence of nasal, skin, and asthmatic allergic symptoms.

Conclusions

Our results indicated that 2 SNPs in the MD-2 promoter region were significantly associated with Der p 2-specific Ig E, and thereby suggest that these SNPs may play a major role in susceptibility to Der p 2-triggered immune responses in a Taiwanese population.  相似文献   
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National and ethnic mutation databases provide comprehensive information about genetic variations reported in a population or an ethnic group. In this paper, we present the Moroccan Genetic Disease Database (MGDD), a catalogue of genetic data related to diseases identified in the Moroccan population. We used the PubMed, Web of Science and Google Scholar databases to identify available articles published until April 2013. The Database is designed and implemented on a three-tier model using Mysql relational database and the PHP programming language. To date, the database contains 425 mutations and 208 polymorphisms found in 301 genes and 259 diseases. Most Mendelian diseases in the Moroccan population follow autosomal recessive mode of inheritance (74.17%) and affect endocrine, nutritional and metabolic physiology. The MGDD database provides reference information for researchers, clinicians and health professionals through a user-friendly Web interface. Its content should be useful to improve researches in human molecular genetics, disease diagnoses and design of association studies. MGDD can be publicly accessed at http://mgdd.pasteur.ma.  相似文献   
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目的:研究亚甲基四氢叶酸还原酶(methylenetetrahydrofolate reductase,MTHFR)基因rs1801133位点多态性与非综合征性唇腭裂(NSCL/P)的关系。方法:采用聚合酶链反应-限制性片段长度多态性方法,检测334例非综合征性唇腭裂患者和314例正常对照组的MTHFR基因rs1801133位点的多态性。结果:MTHFR基因rs1801133位点基因型频率分布符合Hardy-Weinberg平衡;MTHFR基因rs1801133位点基因型及等位基因的分布在NSCL/P组与对照组之间均无统计学意义(P>0.05)。结论:MTHFR基因rs1801133位点多态性与山西人群非综合征性唇腭裂的发生无关。  相似文献   
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