AGER -429T/C Is Associated with an Increased Lung Disease Severity in Cystic Fibrosis

The clinical course of cystic fibrosis (CF) varies between patients bearing identical CFTR mutations, suggesting the involvement of modifier genes. We assessed the association of lung disease severity with the variant AGER -429 T/C, coding for RAGE, a pro-inflammatory protein, in CF patients from the French CF Gene Modifier Study. We analyzed the lung function of 967 CF patients p.Phe508del homozygous. FEV₁ was analyzed as CF-specific percentile adjusted on age, height and mortality. AGER -429T/C polymorphism was genotyped and its function was evaluated in vitro by measurement of the luciferase activity. AGER -429 minor allele (C) was associated with poorer lung function (p = 0.03). In vitro, the promoter activity was higher in cells transfected with AGER -429C compared to cells transfected with the AGER -429T allele (p = 0.016 in BEAS-2B cells). AGER seems to be a modifier gene of lung disease severity in CF, and could be an interesting biomarker of CF airway inflammation. The functional promoter AGER -429C variant is associated with an increased RAGE expression that can lead to an increased lung inflammation and a more severe lung disease.     

Polymorphisms in genes involved in the inflammatory response and interaction with NSAID use or smoking in relation to lung cancer risk in a prospective study

Lung cancer risk was investigated in relation to single nucleotide polymorphisms in genes involved in the inflammatory response. The aim was to see if polymorphisms modifying the inflammatory response are associated with risk of lung cancer and if there were interactions between the same polymorphism and factors, which modify an inflammatory response, such as smoking status, duration, and intensity, and use of NSAID. The functional SNPs IL-1B T-31C, IL6 G-174C, IL8 T-251A, IL10 C-592T, COX2 C8473T, COX2 A-1195G and PPARgamma2 Pro(12)Ala were included. A case-cohort study including 428 lung cancer cases and a sub-cohort of 800 persons was nested within a population-based prospective study of 57,053 individuals. Variant allele carriers of IL-1B T-31C were at increased risk of lung cancer (IRR=1.51, 95% CI=1.08-2.12). There was interaction between the polymorphism COX-2 T8473C and smoking status. Thus, non-smoking variant allele carriers were at 5.75-fold (95% CI=1.25-26.43) higher risk of lung cancer than for homozygous wild type allele carriers. Lung cancer risk was similar for all genotype carriers among past and current smokers. There were, however, very few non-smoking lung cancer cases. There was interaction between IL-1B T-31C, COX-2 A-1195G and PPARgamma2 Pro(12)Ala and NSAID use in relation to lung cancer risk. For the two latter, NSAID use was only associated with a lower cancer risk among homozygous wild type allele carriers. p for interaction was 3 x 10(-6) for COX-2 A-1195G and 9 x 10(-5) for PPARgamma2 Pro(12)Ala. The results suggest that NSAID use may modify risk of lung cancer differently depending on the genotype.     

IL6 and IL1B polymorphisms are associated with fat mass in older men: the MrOS Study Sweden

There is growing evidence that immune functions are linked to the regulation of body fat. Our studies of knockout mice indicate that both endogenous interleukin (IL)-6 and IL-1 can suppress mature-onset obesity. We now investigated whether four common polymorphisms of the IL6 and IL1 systems are associated with the fat mass measured with dual-energy X-ray absorptiometry (DXA) in elderly men (n = 3,014). The study subjects were from the Swedish part of the MrOS multicenter population study and 69-81 years of age. The IL6 -174 G>C (Minor allele frequency (MAF) = 48%) gene promoter polymorphism was associated with the primary outcome total fat mass (P = 0.006) and regional fat masses, but not with lean body mass. The IL1B -31T>C (MAF = 34%) polymorphism was also associated with total fat (P = 0.007) and regional fat masses, but not lean body mass. The IL-1 receptor antagonist (IL-1ra) gene (IL1RN) +2018 T>C (MAF = 27%) polymorphism (in linkage disequilibrium (LD) with a well-studied variable number tandem repeat of 86 base pair (bp)) and IL1B +3953 C>T (MAF = 26%) polymorphism were not associated with total fat mass. In conclusion, the IL-1 and IL-6 systems, shown to suppress mature-onset obesity in experimental animals, contain gene polymorphisms that are associated with fat, but not lean, mass in elderly men.     

Il6 gene promoter polymorphism (-174G/C) influences the association between fat mass and cardiovascular risk factors

During the last decades, the prevalence of obesity has increased rapidly among young people. A polymorphism in the promoter region of the IL6 gene (-174G/C), has been previously reported to be involved in obesity and metabolic syndrome development. Therefore, the aim of the study was to examine whether the IL6-174G/C polymorphism influence the association of body fat with low-grade inflammatory markers and blood lipids and lipoproteins in Spanish adolescents. 504 Spanish adolescents participating in the AVENA study were genotyped for the-174G/C polymorphism of the IL6 gene. Anthropometric and body composition measurements were taken and blood samples were collected for plasma molecules determinations. No differences between genotypes were observed in anthropometric values, body composition measurements and plasma markers concentration. Physical activity level differ between genotypes with subjects carrying the C allele of the polymorphism being significantly (p<0.05) more active than GG subjects. The association between body fat mass and plasma glucose was influenced by the -174G/C polymorphism of the IL6 gene. Subjects carrying the C allele of the mutation seem to have higher values of lipoprotein (a) and C-reactive protein as their percentage of body fat mass increase. Our results suggest that this promoter polymorphism influences the association between adiposity and some plasma markers.     

Association of the solute carrier family 11 member 1 gene polymorphisms with susceptibility to leprosy in a Brazilian sample

Natural resistance-associated macrophage protein 1/solute carrier family 11 member 1 gene (Nramp1/Slc11a1) is a gene that controls the susceptibility of inbred mice to intracellular pathogens. Polymorphisms in the human Slc11a1/Nramp1 gene have been associated with host susceptibility to leprosy. This study has evaluated nine polymorphisms of the Slc11a1/Nramp1 gene [(GT)n, 274C/T, 469+14G/C, 577-18G/A, 823C/T, 1029 C/T, 1465-85G/A, 1703G/A, and 1729+55del4] in 86 leprosy patients (67 and 19 patients had the multibacillary and the paucibacillary clinical forms of the disease, respectively), and 239 healthy controls matched by age, gender, and ethnicity. The frequency of allele 2 of the (GT)n polymorphism was higher in leprosy patients [p = 0.04, odds ratio (OR) = 1.49], whereas the frequency of allele 3 was higher in the control group (p = 0.03; OR = 0.66). Patients carrying the 274T allele (p = 0.04; OR = 1.49) and TT homozygosis (p = 0.02; OR = 2.46), such as the 469+14C allele (p = 0.03; OR = 1.53) of the 274C/T and 469+14G/C polymorphisms, respectively, were more frequent in the leprosy group. The leprosy and control groups had similar frequency of the 577-18G/A, 823C/T, 1029C/T, 1465-85G/A, 1703G/A, and 1729+55del4 polymorphisms. The 274C/T polymorphism in exon 3 and the 469+14G/C polymorphism in intron 4 were associated with susceptibility to leprosy, while the allele 2 and 3 of the (GT)n polymorphism in the promoter region were associated with susceptibility and protection to leprosy, respectively.     

Polymorphisms of TNFalpha, IL1beta, and IL1RN genes in chronic obstructive pulmonary disease

It is recognized that genetic factors play a role in the susceptibility to COPD. COPD is characterized by airflow limitation. Chronic inflammation causes small airway disease and parenchymal destruction, leading to the airflow limitation. Polymorphisms in pro-inflammatory cytokine genes may confer a risk for the development of COPD. A case-control association study was performed in Japanese population (88 COPD patients and 61 controls) and Egyptian population (106 patients and 72 controls). Genotype and allele frequencies of the TNFalpha -308 G/A and +489 G/A polymorphisms, the IL1beta -511 C/T, -31 T/C, and +3954 C/T polymorphisms, and a VNTR polymorphism in intron 2 of the IL1RN gene were investigated. In addition, pairwise haplotype frequencies were analyzed. When studied independently, none of the polymorphisms were associated with the development of COPD in both populations. However, in the Egyptian population, the distributions of the haplotype (IL1beta -31 T/C : IL1beta +3954 C/T) were significantly different between the COPD patients and the controls (p(corr)=0.0037). Our findings suggest that this haplotype within the IL1beta gene may be involved in the pathogenesis of COPD and that the genetic factors of COPD susceptibility might be different between different populations.     

The interleukin-6 (-174) G/C promoter polymorphism is associated with type-2 diabetes mellitus in Native Americans and Caucasians

Chronic low-grade activation of the immune system may play a role in the pathogenesis of type-2 diabetes mellitus (T2DM). Interleukin-6 (IL6), a powerful inducer of hepatic acute phase response, has been implicated in the etiology of insulin resistance and T2DM. Recently, an IL6 promoter polymorphism (G/C) at position -174 was found to be associated with measures of insulin sensitivity. Because we have previously found an association between high IL6 levels and insulin resistance in both Pima Indians - a population with high rates of insulin resistance and T2DM - and Caucasians, we aimed to assess whether the IL6 promoter polymorphism is associated with T2DM in these populations. We genotyped the IL6 (-174) G/C polymorphism using pyrosequencing in 463 Native Americans and by PCR-RFLP in 329 Spanish Caucasians. Among the Spanish Caucasian subjects, there was a significant difference in genotypic distribution between diabetic and non-diabetic subjects (P=0.028); the GG genotype was more common in diabetic (0.40) than in non-diabetic (0.29) subjects. The G allele was much more frequent in the Native American sample, and among a sample of 143 cases and 145 controls, the GG genotype was significantly more common in diabetic subjects (P=0.019). When this sample population was stratified according to ethnic heritage, all 211 subjects who were of full Pima Indian heritage had the GG genotype, whereas in the 77 American Indian subjects with non-Pima admixture, T2DM was associated with IL6 genotype (P=0.001). These findings are consistent with a role for genetic determinants of inflammation in the development of T2DM in both Native Americans and Caucasians.     

Polymorphisms of interleukin-1 and interleukin-6 genes on the risk of ischemic stroke in a meta-analysis

Many epidemiological studies have investigated the associations between polymorphisms of interleukin-1 (IL1) and interleukin-6 (IL6) genes and risk of ischemic stroke (IS), but no conclusions are available because of conflicting results. The aim of this study was to assess the relationships by meta-analysis. The databases of Pubmed, Embase and Wangfang, updated to August 1st, 2011, were retrieved. Odds ratio (OR) and corresponding 95% confidence interval (95% CI) as effect size were calculated by a fixed- or random-effect model. In total, three case-control studies for IL1α-889C/T, eight studies for IL1β-511C/T, eight studies for IL1-Ra and seven studies for IL6-147G/C were included in this meta-analysis. Combined analysis indicated that IL1β-511C/T polymorphism was not overall associated with risk of IS [OR (95% CI)=1.22 (0.85-1.87) for TT vs. CC]. However, when subgroup analyses for countries were conducted, the results indicated that T allele was associated with increased risk of IS for Polish and associated with a trend of increased risk of IS for Chinese although it did not reach statistical significance [TT vs. CC: OR (95% CI)=1.97 (1.22-3.17) for Polish and 1.40 (0.99-1.99) for Chinese]. In addition, overall and subgroup analyses indicated that IL1α-889C/T, IL1-Ra and IL6-147G/C polymorphisms were also not associated with risk of IS [OR (95% CI)=1.21 (0.86-1.70) for TT vs. CC of IL1α-889C/T, 1.22 (0.85-1.75) for RN2/RN2 vs. RN1/RN1 for IL1-Ra and 1.09 (0.84-1.40) for G carriers vs. C carriers for IL6-147G/C]. This study inferred that IL1β-511C/T polymorphism might be moderately associated with increased risk of IS, but no sufficient evidence was available to support any associations between IL1-Ra and IL6-147G/C polymorphisms and IS. We could not draw a conclusion between IL1α-889C/T polymorphism and risk of IS based on the limited data, and further large sample-sized studies were required.     

Interleukin-4 -590T/C polymorphism influences the susceptibility to nonsmall cell lung cancer

Lung cancer is the leading cause of cancer mortality worldwide. Nonsmall cell lung cancer (NSCLC) accounts for most of these cases. Interleukin 4 (IL-4) is a typical pleiotropic T helper 2 cytokine and plays crucial roles in tumor immunology. IL-4 gene -590T/C polymorphism has been shown to be associated with different autoimmune diseases and cancers. The present study evaluated the correlation between this polymorphism and the susceptibility to NSCLC in the Chinese population. The IL-4 variant -590T/C was detected by polymerase chain reaction-restriction fragment length polymorphism in 1072 NSCLC cases and 1126 age-matched healthy controls. Data were analyzed using the Chi-square test. Results showed that frequencies of IL-4 -590 TC, CC genotype, and -590 C allele were significantly lower in patients with NSCLC than in healthy controls (odds ratio [OR]=0.77, 95% confidence interval [CI] 0.64-0.93, p=0.006; OR=0.54, 95% CI 0.38-0.76, p=0.0004; and OR=0.72, 95% CI 0.62-0.83, p=1.1 × 10(-5), respectively). Our data suggest that the -590T/C polymorphism of the IL-4 gene is associated with a decreased susceptibility to NSCLC.     

<Emphasis Type="Italic">IL4</Emphasis> in the 5q31 context: association studies of type 1 diabetes and rheumatoid arthritis in the Spanish population

IL4, the gene coding the prototypic Th2 cytokine, has been frequently studied in the context of several inflammatory conditions, but conclusive results have not been obtained. This gene is located in the 5q31-33 complex genetic region, which shows some susceptibility factors to type 1 diabetes (T1D) and rheumatoid arthritis (RA) among other inflammatory conditions. Our aim was to assess the involvement on T1D and RA of IL4 polymorphisms considered individually and in combination with other polymorphisms in 5q31-33, specifically in the OCTN locus, where the L503F polymorphism has been associated with Crohn's disease and other Th1 diseases. We performed a case-control study including 316 T1D patients, 599 RA patients and 540 healthy controls, all of them corresponding to white Spanish individuals. The IL4 single-nucleotide polymorphisms (SNPs) -590C/T (rs2243250) and the OCTN1 exonic SNP L503F (rs1050152) were analysed in all samples. Frequency comparisons of -590C/T and stratified analysis including both cited SNPs were performed using chi-square tests. The -590C/T IL4 SNP was not found associated with T1D or RA when individual analyses were performed. However, a significant association with T1D emerged after stratification by L503F [p=0.02, odds ratio=1.95, 95% CI=1.07-3.55]. The location of the IL4 gene in the complex 5q31-33 genetic region, which contains many genes involved in immunological responses and presents linkage disequilibrium extended along many kilobases, makes necessary to interpret cautiously the previous IL4-association studies.     

CYP7A1基因-204位点A/C变异对启动子活性的影响

CYP7A1（cholesterol 7α-hydroxylase ）在胆固醇向胆汁酸代谢途径中起着至关重要的作用.为研究该基因启动子区-204位点A/C多态性是否影响基因表达, 利用荧光素酶作为报告基因,将含有A或C等位基因的启动子区片段分别正向和反向插入不含启动子的pGL3 basic质粒载体中,再以重组体转染4种细胞株,采用双荧光素酶报告基因检测系统测定酶活性并进行比较.实验结果表明,2种基因型的正向序列启动子活性均高于相应的反向序列,含有A等位基因的启动子片段活性比含有C等位基因的片段低约1/3.TRANSFAC数据库分析显示,当-204位点等位基因为C时,可能存在1个Zic3结合位点.研究结果提示,CYP7A1基因启动子区-204位点A/C变异可减少启动子活性从而影响基因表达,其原因可能为1个潜在的Zic3结合位点的丧失.