C(-260)T polymorphism in the promoter of CD 14 gene is not associated with myocardial infarction in the Tunisian population

Recent findings suggest that inflammation plays a role in atherosclerosis and its acute complications. Several known mechanisms may play at least a partial role in this process. One of the most likely mechanisms involves lipopolysaccharide (LPS) and its receptor, CD14. The C(− 260)T single nucleotide polymorphism (rs2569190) in the promoter region of the CD14 receptor gene has been reported to be associated with a higher risk of MI. Others studies, however, have not corroborated these findings. Considering the contradictory results, the aim of the present study was to investigate the possible association between the CD14 C(− 260)T polymorphism and the risk of MI in the Tunisian population.A total of 321 Tunisian patients with MI and 344 healthy controls were included in the study. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. The frequency of TT homozygous genotype for the CD14 C(− 260)T polymorphism was 26.2% in MI patients and 27.0% in the control group. However, the genotype distribution and allele frequencies were not significantly different between MI and controls subjects. Moreover, the odds ratio for MI associated with the TT genotype failed to reach statistical significance (OR = 1.22; 95% CI: 0.85–1.77; p = 0.272).These results do not support the hypothesis that the C−260T polymorphism of CD14 gene contributes to the genetic susceptibility to MI in the Tunisian population studied.     

Polymorphisms in the 5' region of the CD14 gene are associated with eczema in young children

BACKGROUND: Variants in the CD14 gene (CD14) are hypothesized to be associated with atopic disorders. However, most studies have only investigated one polymorphism in this gene. OBJECTIVE: We sought to study the association of 5 single nucleotide polymorphisms (SNPs) in the 5' flanking region of CD14 with eczema and serum IgE levels in young children. METHODS: We genotyped 5 SNPs in an approximately 6.5-kb region in the 5' region of CD14 in 344 2-year-old white children from 2 birth cohorts in the northeastern United States. We examined the relation of both single SNPs and haplotypes in CD14 with the atopic outcomes. RESULTS: Two SNPs were significantly associated with eczema. In dominant models adjusted for potential confounders, SNP rs2569193 was associated with significantly decreased risk for eczema (odds ratio [OR] for CT/TT vs CC, 0.5; 95% CI, 0.3-0.8), whereas SNP rs2569190 (also reported as the C-159T) was associated with significantly increased risk for eczema (OR for CT/TT vs CC, 2.3; 95% CI, 1.4-3.8). The CT/TT genotypes of SNP rs2569190 also had higher geometric means of serum IgE than the CC genotype (24.6 vs 15 IU/mL, P = .025). Haplotype analyses provided results similar to those of the single SNP analyses. CONCLUSIONS: Our results contradict previous reports that have found a protective effect of the T allele of SNP rs2569190 (C-159T) against atopic disorders. Nevertheless, these results confirm the importance of polymorphisms in CD14 in the development of atopy, and future studies of this gene region will need to account for linkage disequilibrium and environmental exposures unique to the study population.     

Searching for links between endotoxin exposure and pregnancy loss: CD14 polymorphism in idiopathic recurrent miscarriage

PROBLEM: Lipopolysaccharide (LPS) (endotoxin) is a well-known inducer of abortions in mice. In addition it has been proposed that gut-derived LPS of gram-negative bacteria may play a role in triggering idiopathic recurrent miscarriage (IRM) in humans. CD14 is one of the key molecules that mediates the effects of LPS. Promoter region polymorphism (-159C/T) in the CD14 gene is functionally important by regulating CD14 levels. High-producing CD14 genotype (TT) associates with deleterious effects of gut-derived LPS in hepatic cirrhosis in humans. It is not known whether women with IRM are genetically more prone to suffer from toxic effects of LPS. METHOD OF STUDY: By using polymerase chain reaction we analyzed the CD14 promoter region polymorphism in 38 women with IRM and in 127 normal controls of Finnish origin. RESULTS: There were no significant differences in the CD14 (-159C/T) allele or the genotype frequencies between the IRM women and the controls. However, there was a trend associating the presence of the T allele with increased odds of miscarriage. CONCLUSIONS: Although we were not able to find a statistically significant association between CD14 genotypes and IRM in our relatively small study population, a further study with a larger sample size is warranted to explore the role of high-producing CD14 genotypes in IRM. Also studies highlighting environmental LPS triggers and other intrinsic mediators of LPS signalling are needed to solve the enigmatic role of LPS in IRM in humans.     

The role of lipopolysaccharide in the development of atopy in humans

Atopy is a highly prevalent condition and remains the single biggest risk factor for asthma. Although atopy has a heritable component, the time frame of the increase in the prevalence indicates that it is not due to genetic factors alone. The relationship between allergen exposure and sensitization is complex. Lipopolysaccharide (LPS) and its bioactive moiety endotoxin are common to all gram‐negative bacteria, and have been used as a surrogate of microbial load. Endotoxin can be readily measured in dust collected from homes. Some studies have demonstrated a clear inverse dose–response relationship between exposure to endotoxin and the risk of atopy but this finding has not been reproduced in all studies. Our innate immune system recognizes LPS readily via the LPS signal transduction pathway, which has the trimolecular complex of CD14/TLR4/MD2 at the core. A common single‐nucleotide polymorphism in the promoter region of CD14 rs2569190 C to T (CD14/?260 or CD14/?159) has been associated with elevated sCD14. Although early studies suggested that this variant was associated with more severe atopy, this finding was not uniformly replicated. It has now been demonstrated in four independent populations that high exposure to endotoxin in the domestic environment is protective against the development of atopy, but only among carriers of the C allele, that is, the environmental exposure is only relevant when taken in the context of the genotype. Furthermore, this interaction is biologically plausible. We propose that neither the environmental exposure nor the genotype in isolation is sufficient to cause complex diseases like asthma and atopy, but disease results from the one acting in the context of the other, of which CD14 and endotoxin is one example contributing to the risk for atopy. Cite this as: A. Simpson and F. D. Martinez, Clinical & Experimental Allergy, 2010 (40) 209–223.     

中国广西人白细胞介素-21基因rs2221903 T/C遗传多态性研究

目的:了解白细胞介素-21(IL-21)基因单核苷酸多态性(SNP)各等位基因及基因型在中国广西地区人群中的分布频率,比较其在不同种族间分布的差异。方法:采用单碱基延伸的PCR技术和DNA测序法检测199例中国广西人的IL-21基因rs2221903 T/C多态性,并结合人类基因组计划(Hapmap)公布的欧洲人、非洲人、日本人和中国北京人的SNP分型数据,比较分析广西人与其他种族人群的基因型及等位基因分布频率的差异。结果:广西人IL-21基因型TT、TC和CC频率分别为75.38%、23.62%和1.01%;等位基因T、C频率分别为87.19%和12.81%。其基因型频率在男女组间比较差异无统计学意义(P>0.05)。广西人与欧洲和非洲人群比较,IL-21基因多态性分布频率差异均有统计学意义(P<0.05);而与日本人和中国北京人比较差异无统计学意义(P>0.05)。结论:在中国广西人群中存在IL-21基因多态性,且与其他种族人群比较存在显著性差异,这种差异对于人类学的研究可能起重要的作用。     

Association between the CD14−260C>T gene polymorphism and susceptibility to myocardial infarction: Evidence from case−control studies

Numerous published studies have investigated the relationship between the CD14?260C>T (rs2569190) polymorphism and the risk of myocardial infarction (MI). However, the results are still conflicting and inconclusive. Potentially eligible published articles were searched in four databases including PubMed, Web of Science, EMBASE and Chinese Biomedical Database (CBM). The odds ratio (OR) with its 95% confidence interval (CI) was used to estimate the strength of the associations. Thirteen papers including 17 case–control studies were included, reporting a total of 6,443 MI patients and 6,315 controls. A significant increase in overall MI susceptibility was identified in the homozygote model. In the subgroup analysis, with respect to the type of MI, a significantly increasing acute MI susceptibility was found in the homozygote model. In the subgroup analysis for ethnicity, a significant increased susceptibility was found in Asian populations in allele, homozygote, recessive and dominant models. However, no significant association was found among Caucasian populations. In conclusion, there may be a moderate association between the CD14?260C>T polymorphism and acute MI susceptibility. This association may be different between ethnicities with the CD14?260C>T polymorphism being a risk factor for myocardial infarction in Asian populations.     

The functional genetic variation in the PTPN22 gene has a negligible effect on the susceptibility to develop inflammatory bowel disease

The aim of this study was to assess the possible association between the protein tyrosine phosphatase non-receptor 22 (PTPN22) gene 1858C-->T (rs2476601, encoding R620W) polymorphism and inflammatory bowel disease (IBD). Our study population consisted of 1113 IBD [544 ulcerative colitis (UC) and 569 Crohn's disease (CD)] patients and 812 healthy subjects. All the individuals were of Spanish white origin. Genotyping of the PTPN22 gene 1858C-->T polymorphism was performed by real time polymerase chain reaction technology, using TaqMan 5'-allelic discrimination assay. The frequency of the PTPN22 1858T allele in healthy subjects was 6.2% compared with 6.7% in the UC patients and 5.1% in Crohn's patients. No statistically significant differences were observed when the PTPN22 1858C-->T allele and genotype distribution among CD patients, UC patients and healthy controls were compared. These results indicate that the PTPN22 1858C-->T polymorphism does not appear to play a major role in IBD predisposition in our population.     

NOD1基因多态性与儿童吉兰-巴雷综合征的相关性研究

目的 探讨陕西地区汉族儿童中,NOD1基因多态性与吉兰-巴雷综合征(Guillain-Barre syndrome,GBS)易感性的关系.方法 选择201 3年1月至201 6年10月治疗的1 12例GBS患儿作为GBS组,同时随机选择同期体检的健康儿童110例作为对照组,采用聚合酶链反应-限制性片段多态性法检测NOD-1基因rs2075820和rs7789045位点多态性.结果 rs2075820位点多态性在显性模型、隐性模型和等位基因模型下与儿童GBS易感性相关(P=0.013、P=0.016、P=0.005).将GBS组分为不同亚型,rs2075820位点多态性在隐性模型和等位基因模型下与急性炎性脱髓鞘性多发神经病(acute inflammatory demyelinating polyneuropathy,AIDP)易感性相关(P=0.018、P=0.015);在显性模型、隐性模型和等位基因模型下与急性运动轴索性神经病(acute motor axonal neuropathy,AMAN)易感性相关(P=0.024、P=0.004、P=0.002);rs2075820位点多态性在各模型下均与急性运动感觉轴索性神经病(acute motor-sensory axonal neuropathy,AMSAN)易感性无关(均P＞0.05).rs7789045位点多态性在各模型下与儿童GBS及各亚型易感性均无关(均P＞0.05).rs2075820和rs7789045多态性与病情严重程度和预后均无显著相关性.结论 NOD-1基因rs2075820多态性与GBS遗传易感性相关.     

四个E-选择素基因的多态性与哈尼族原发性高血压相关性研究

目的探讨E－选择素基因rs3917408G／T、rs5361A／C、rs5368C／T和rs3917429C／T等4个错义突变与哈尼族原发性高血压的关系。方法采用PCR测序技术，对云南哈尼族172例原发性高血压患者和133例正常对照的E－选择素基因的rs3917408G／T、rs5361A／C、rs5368C／T和rs3917429C／T突变进行检测。结果在哈尼族原发性高血压组，rs3917408T、rs5361C、rs5368T和rs39t7429T等位基因频率分别为2％、7％、28．8％和6．1％，正常对照组相应的等位基因频率分别为4％、4．9％、21．8％和1．1％，其中原发性高血压组rs3917429位点T等位基因频率显著高于正常对照组（P〈0．01），其余突变点两组之间的等位基因频率比较差异均无显著性（P〉0．05）。结论E－选择素基因rs3917429位点T等位基因与哈尼族原发性高血压相关。     

Relationship between interleukin-1 type 1 and 2 receptor gene polymorphisms and the expression level of membrane-bound receptors

The biological activity of the multifunctional cytokine interleukin-1 (IL-1) is mediated by its receptors. The aim of this study was to determine if an association exists between single nucleotide polymorphisms (SNPs) in the IL-1 type 1 and 2 receptor genes (IL1R1 and IL1R2) and the expression level of membrane-bound IL1Rs on subpopulations of mononuclear cells or serum levels of soluble IL-1 receptors. It was observed that healthy individuals with the genotype TT in SNP rs2234650:C>T had a lower percentage of intact CD14⁺ monocytes expressing IL1R1 on their surface. The SNP rs4141134:T>C in IL1R2 has also been associated with the percentage of intact CD3⁺ T cells expressing IL1R2. Furthermore, individuals carrying the CC allele of SNP rs4141134:T>C and the TT allele of SNP rs2071008:T>G in IL1R2 had a lower density of IL1R2s on the surface of CD14⁺ monocytes in lipopolysaccharide (LPS)-stimulated PBMC cultures. In summary, this study demonstrated that IL-1 receptor gene polymorphisms could be one of the factors influencing the expression of membrane-bound IL-1 receptors (IL1R) on immunocompetent cells.     

Genetic diversity of CD14, CD28, CTLA-4 and ICOS gene promoter polymorphism in African and American sickle cell disease

Variable immune response to external stimuli remains a major concern in sickle cell disease (SCD), with such responses predicted to be contributors to disease pathogenesis. Elucidating the diversity of host genes contributing to immune response would assist to clarify differing outcomes among and between disease groups. We hypothesize that there is a significant interethnic diversity in the CD14 (rs2569190), CD28 (rs35593994), CTLA-4 (rs5742909) and ICOS (rs4404254) gene polymorphisms among and between SCD groups. We genotyped single nucleotide polymorphisms of the 4 loci among African and African American SCD and control groups and between SCD groups. In all, 375 individuals from Mali (145 SCD and 230 controls) and 700 DNA samples from the United States (321 SCD and 379 controls) were subjected to a PCR-RFLP assay. We found no intraethnic difference in genotypic and allelic frequencies of the 4 loci among Africans and African Americans, potentially significant in disease association studies, including a similar observation for interethnic frequencies of CD28, CTLA-4 and ICOS genes, but not CD14. The CD14 (rs2569190) gene promoter demonstrated a significant difference (p < 0.02) between African and African American SCD groups, with the mutant variant (−159 T/T) more frequent (p < 0.0002) in African American SCD (38.9% versus 26.2%). The higher frequency of CD14 mutants among African Americans without an accompanying defect in CD28, CTLA-4 and ICOS diversity possibly indicates a defective innate response, driven by CD14, is untethered to downstream T cell differentiation or effector function. Additionally, we show that CD28 (rs35593994) mutant variants have no impact on T cell differentiation, as the ICOS gene provides an alternative pathway to override this impairment. We conclude that in spite of the defect in CD14, T cell selection and differentiation is unimpeded and a robust adaptive immune response initiated.     

二甲基精氨酸二甲基氨基酸水解酶基因多态性与冠心病的相关性研究

目的:研究中国人群二甲基精氨酸二甲基氨基酸水解酶(DDAH)基因单核苷酸多态性(SNP)与冠状动脉性心脏病(coronary heart disease,CHD)的关系。方法:从山西医科大学第二医院选取冠心病患者165例和匹配的对照组192例。并记录所有研究对象的病史、体格检查等临床资料及其它流行病学资料,采取聚合酶链式反应和限制性酶切片段长度多态性分析方法(PCR-RFLP)检测各组DDAH2基因rs805305位点C/G的基因型并统计各组的基因型频率。用连接酶检测反应(LDR)-测序分型方法检测各组基因rs2272592位点G/A的基因型并统计各组的基因型频率。结果:冠心病组rs805305和rs2272592基因型频率与对照组之间相比较均无显著差异(P0.05)。并在校正了年龄、性别、高血压史、糖尿病史、甘油三酯和胆固醇等传统危险因素的影响后,这种相关性依然不存在。结论:DDAH2基因rs805305位点C/G多态性和rs2272592位点G/A多态性可能与中国人群冠心病发病不相关。     

Tumour necrosis factor (TNF) gene polymorphism influences TNF-α production in lipopolysaccharide (LPS)-stimulated whole blood cell culture in healthy humans

TNF-α is involved in infectious and immuno-inflammatory diseases. Different individuals may have different capacities for TNF-α production. This might determine a predisposition to develop some complications or phenotypes of these diseases. The aims of our study were to assess the inter-individual variability of TNF-α production and to correlate this variability to a single base pair polymorphism located at position ?308 in TNF gene. We studied 62 healthy individuals. TNF-α production after LPS stimulation was evaluated using a whole blood cell culture model. The TNF gene polymorphism was studied by an allele-specific polymerase chain reaction. Other cytokines produced in the culture, soluble CD14 concentrations and expression of CD14 on blood cells were also measured. Among the 62 individuals, 57 were successfully genotyped. There were 41 TNF1 homozygotes and 16 TNF1/TNF2 heterozygotes. TNF-α production after LPS stimulation of whole blood cell culture was higher among TNF2 carriers than among TNF1 homozygotes (929 pg/ml (480–1473 pg/ml) versus 521 pg/ml (178–1307 pg/ml); P < 0.05). This difference was even more significant after correction of TNF-α production for CD14 expression on blood cells. In conclusion, the single base pair polymorphism at position ?308 in the TNF gene may influence TNF-α production in healthy individuals.     

Evaluation of the CD14/-260 polymorphism and house dust endotoxin exposure in the Barbados Asthma Genetics Study

BACKGROUND: Both a functional promoter polymorphism in the gene encoding CD14 (C-260T) and exposure to endotoxin are believed to play key roles in modulating the immune response and expression of atopic disease. OBJECTIVE: We aimed to evaluate the role of the CD14 C-260T polymorphism in a population of African descent and to test for interaction between this genotype and house dust endotoxin (HDE) exposure on atopic phenotypes. METHODS: Asthmatic probands and their families were recruited as part of the Barbados Asthma Genetics Study. The C-260T polymorphism and two additional CD14 promoter markers (G-1461T, C-1721T) were genotyped. Endotoxin was measured in house dust samples. RESULTS: Using a Family-Based Association Test, the C-260T allele appeared to be protective against asthma ( z = -2.444; P = .015) and asthma severity ( z = -2.615; P = .009) under a recessive model. No significant associations were observed for the G-1461T and C-1721T markers both individually and in haplotypes. In a case-control analysis, the CD14 TT genotype was found to reduce risk of asthma compared with the CD14 CC/CT genotypes (odds ratio [OR], 0.26; 95% CI, 0.14-0.49) and was associated with lower asthma severity scores ( P < .002). The TT genotype might protect against asthma for individuals with low HDE (OR, 0.09; 95% CI, 0.03-0.24), but may be a risk factor for individuals with high HDE (OR, 11.66; 95% CI, 1.03-131.7), suggesting a gene-environment interaction. CONCLUSION: These data suggest that the CD14-260 polymorphism may play a role in controlling risk to atopic disease and underscore the importance of incorporating key environmental exposures into studies of genetic risk factors.     

Relevance between HLA-DP gene rs2281388 polymorphism and hepatocellular carcinoma risk

Purpose: We carried out this study to find out the relevance between rs2281388 T/C polymorphism of human leukocyte antigen (HLA) gene and hepatocellular carcinoma (HCC) risk in Chinese Han population. Methods: The method of polymerase chain reaction (PCR) was applied to amplify the genomic DNA. Then the PCR products were sequenced to test the HLA-DP gene rs2281388T/C polymorphism of the case and control groups. Odds ratios (ORs) and 95% confidence interval (95% CIs) were utilized to evaluate the potential correlation between rs2281388 variants and HCC risk. Results: We analyzed the rs2281388 polymorphism distribution among the clinical pathological features. The results showed that there existed a significant statistic correlation between rs2281388T/C polymorphism of HLA-DP gene and HBsAg feature, and no significant correlation was found between rs2281388 and other clinical features. Further analysis showed that the TT genotype of rs2281388 was significantly correlated with HCC risk, and the same to T allele, but there was no significant difference of CT genotype distribution in case and control groups. Conclusion: TT genotype and T allele of HLA-DP gene rs2281388 polymorphism may increase the risk of HCC.