中国人CYP1A1和GSTM1基因多态性及其对个体肺癌易感性的联合效应

目的 在中国江苏肺癌患者和对照人群中,检测CYP1A1 Ile/Val,GSTM1 /0遗传多态性的各基因型及其联合基因型的分布,探讨这些基因型与肺癌个体易感性的关系。方法 配对的病例－对照组各106例,静脉血制备DNA。分别应用等位基因特异性（allele-specific,AS)-PCR和多重差别（multidifferential,MD)-PCR,检测CYP1A1 Ile/Val和GSTM1＋／0的等位基因型。结果 CYP1A1少见等位基因Val/Val纯合子及其与GSTM1基因缺失纯合子（0／0）的联合基因个体,与对照常见基因型个体相比,增加了对肺癌的易感性,其相对危险度（odds ratio,OR)分别为4．02（P＝0．03）和9．38（P＝0．04）;GSTM10／0纯合子及其与CYP1A1 Ile/Val杂合子的联合基因型个体,显著增加了肺癌易感性,其OR值分别是1．92（P＝0．019）和3．27（P＝0．01）。结论 中国江苏人群中,少见基因型CYP1A1 Val/Val,GSTM10/0增加了个体肺癌易感性,在肺癌发生中,上述两种易感基因型间存在协同或相乘作用。     

Polymorphisms in inflammasome' genes and susceptibility to HIV-1 infection

The involvement of inflammasome genes in the susceptibility to HIV-1 infection was investigated. Twelve single nucleotide polymorphisms within NLRP1, NLRP3, NLRC4, CARD8, CASP1, and IL1B genes were analyzed in 150 HIV-1-infected Brazilian subjects and 158 healthy controls. The 2 polymorphisms rs10754558 in NLRP3 and rs1143634 in IL1B were significantly associated to the HIV-1 infection. These findings supported the previously hypothesized involvement of NALP3-inflammasome in HIV-1 pathogenesis, underlining once more the key role of inflammation and innate immunity in the susceptibility to HIV-1 infection.     

Polymorphisms in chemokine receptor genes and susceptibility to Kawasaki disease

Kawasaki disease (KD) is an acute vasculitis occurring in young children. Its aetiology is unknown, but an infectious agent is assumed. Increased levels of proinflammatory cytokines and chemokines have been reported in KD. Genetic variation in these genes and the receptors for these genes could influence the regulation of cytokines and chemokines. In a case-control study of 170 Dutch Caucasian KD patients and 300 healthy Dutch Caucasian controls, common genetic variants in chemokine receptor genes CCR3, CCR2, CCR5, CX3CR1, CXCR1 and CXCR2 were analysed. Of the eight studied single nucleotide polymorphisms (SNPs) in the CCR3-CCR2-CCR5 gene cluster, four showed a significant association with susceptibility to KD. Moreover the CCR5-Delta32 was observed with an allele frequency of 10.7% in the control population compared to 6.5% in the KD patients (P = 0.04). Two haplotypes of the CCR3-CCR2-CCR5 gene-cluster appear to be at risk haplotypes for KD and one a protective haplotype. No association was observed with the studied SNPs in CX3CR1, CXCR1 and CXCR2. In conclusion, in a Dutch cohort of KD patients an association of KD occurrence with common genetic variants in the chemokine receptor gene-cluster CCR3-CCR2-CCR5 was observed.     

Genome-wide search for sarcoidosis susceptibility genes in African Americans

Sarcoidosis, a systemic granulomatous disease of unknown etiology, likely results from an environmental insult in a genetically susceptible host. In the US, African Americans are more commonly affected with sarcoidosis and suffer greater morbidity than Caucasians. We searched for sarcoidosis susceptibility loci by conducting a genome-wide, sib pair multipoint linkage analysis in 229 African-American families ascertained through two or more sibs with a history of sarcoidosis. Using the Haseman-Elston regression technique, linkage peaks with P-values less than 0.05 were identified on chromosomes 1p22, 2p25, 5p15-13, 5q11, 5q35, 9q34, 11p15 and 20q13 with the most prominent peak at D5S2500 on chromosome 5q11 (P=0.0005). We found agreement for linkage with the previously reported genome scan of a German population at chromosomes 1p and 9q. Based on the multiple suggestive regions for linkage found in our study population, it is likely that more than one gene influences sarcoidosis susceptibility in African Americans. Fine mapping of the linked regions, particularly on chromosome 5q, should help to refine linkage signals and guide further sarcoidosis candidate gene investigation.     

Polymorphisms of innate immunity genes and susceptibility to lymphatic filariasis

We examined 906 residents of an area of Papua New Guinea where bancroftian filariasis is endemic for genetic polymorphisms in three innate immunity genes suspected of contributing to susceptibility to infection and lymphatic pathology. Active infection was confirmed by the presence of blood-borne microfilariae and circulating filarial antigen in plasma. Disease was ascertained by physical examination for the presence of overt lymphedema (severe swelling of an arm or leg) or hydrocele. There was no association of infection status, lymphedema of an extremity, or hydrocele with chitotriosidase genotype (CHIT1). Polymorphisms of toll-like receptor-2 and toll-like receptor-4 genes (TLR4 A896G; TLR2 T2178A, G2258A) were not detected (N=200-625 individuals genotyped) except for two individuals heterozygous for a TLR2 mutation (C2029 T). These results indicate that a CHIT1 genotype associated previously with susceptibility to filariasis in residents of southern India and TLR2 and TLR4 polymorphisms do not correlate with infection status or disease phenotype in this Melanesian population.     

Polymorphisms of dioxin receptor complex components and detoxification-related genes jointly confer susceptibility to advanced-stage endometriosis in the taiwanese han population

Citation Wu C‐H, Guo C‐Y, Yang J‐G, Tsai H‐D, Chang Y‐J, Tsai P‐C, Hsu C‐C, Kuo P‐L. Polymorphisms of dioxin receptor complex components and detoxification‐related genes jointly confer susceptibility to advanced‐stage endometriosis in the Taiwanese Han population. Am J Reprod Immunol 2012; 67: 160–168 Problem To establish a multilocus model for studying the effect of dioxin receptor complex components and detoxification‐related enzymes on advanced endometriosis. Method of study Six single‐nucleotide polymorphisms (SNPs) and two deletion polymorphisms from eight genes (CYP1A1, CYP1B1, GSTM1, GSTT1, GSTP1, AhR, ARNT, and AhRR) were genotyped. Results In the single SNP analysis, GSTM1 null type and AhRR variant type were associated with a significantly increased risk of endometriosis [odds ratio (OR) = 2.38 and 2.45, respectively]. Using multiple SNPs in the logistic regression for covariates, wild‐type AhR and mutant AhRR combination was significantly higher in patients (67.8%) than in controls (48.0%) (OR = 2.76). On the other hand, mutant AhRR in combination with GSTM1 null genotype was significantly higher in patients (35.5%) than in controls (19.3%) (OR = 6.12). Conclusion Polymorphisms of dioxin receptor complex components and detoxification‐related genes jointly confer susceptibility to advanced‐stage endometriosis in the Taiwanese Han population.     

Polymorphisms of the interferon gamma and interleukin 10 genes in human brucellosis

We genotyped 83 patients with brucellosis and 101 controls to determine the influence of polymorphisms of the interferon gamma (IFNG) and interleukin 10 (IL10) genes on protection against, or susceptibility to, human brucellosis and its complications. The results showed a significant increase in the IFNG +874A/A genotype in patients compared with controls (34% vs. 19%) (P = 0.023, odds ratio = 2.17, 95% confidence interval 1.05–4.51). No significant differences were detected in the frequency distribution of the IL10 genotypes between patients and controls. Similarly, no significant differences were observed in the genotype frequencies of either of the two cytokines between complicated and non‐complicated forms of brucellosis. Persons who are homozygous for the IFNG +874A allele may have a higher risk of contracting brucellosis.     

Polymorphisms in proinflammatory genes and susceptibility to typhoid fever and paratyphoid fever.

Host genetic factors are thought to contribute to susceptibility and outcome in infectious diseases. A polymorphism in a proinflammatory gene, tumor necrosis factor-alpha (TNFA - 308), was recently found to be associated with susceptibility to typhoid fever. As the observation was made in hospitalized patients, a potential confounder could be that the TNFA polymorphism is associated with the severity of established illness resulting in hospital admission rather than susceptibility to disease. We tested whether the association with TNFA - 308 is present also in typhoid fever patients enrolled in a community-based case-control study in an endemic area in Indonesia. Common polymorphisms in other proinflammatory genes were assayed as well. Samples of patients with blood culture-confirmed typhoid fever (n = 90) and paratyphoid fever (n = 26) and fever controls (n = 337) were compared with those of community controls (n = 322). In these groups, we analyzed polymorphisms in TNFA by PCR and RFLP, polymorphisms of IFNG, IL1A, IL1B, IL1R1, TNFRSF1A, CASP1, and CRP by Sequenom MassArray (San Diego, CA), and polymorphisms in IL12B and IFNGR1 by fragment length analysis. The IL1R1 polymorphisms were nearly absent in the Indonesian population. The TNFA - 308 polymorphism was not associated with typhoid fever (OR 0.35, 95% CI 0.1-1.0) in this population. The polymorphisms at TNFA - 238 or in IFNG, IL1A, IL1B, IL12B, TNFRSF1A, IFNGR1, CASP1, and CRP were also not associated with typhoid or paratyphoid fever. We conclude that polymorphisms in proinflammatory genes do not contribute to susceptibility to typhoid fever and, in view of earlier findings, suggest that the TNFA - 308 polymorphism is likely related to severity of established disease rather than to susceptibility per se.     

Polymorphisms of the interferon gamma and interleukin 10 genes in human brucellosis.

We genotyped 83 patients with brucellosis and 101 controls to determine the influence of polymorphisms of the interferon gamma (IFNG) and interleukin 10 (IL10) genes on protection against, or susceptibility to, human brucellosis and its complications. The results showed a significant increase in the IFNG +874A/A genotype in patients compared with controls (34% vs. 19%) (P = 0.023, odds ratio = 2.17, 95% confidence interval 1.05-4.51). No significant differences were detected in the frequency distribution of the IL10 genotypes between patients and controls. Similarly, no significant differences were observed in the genotype frequencies of either of the two cytokines between complicated and non-complicated forms of brucellosis. Persons who are homozygous for the IFNG +874A allele may have a higher risk of contracting brucellosis.     

Polymorphisms and haplotypes of the chromosome locus 17q12-17q21.1 contribute to adult asthma susceptibility in Slovenian patients

One of the major asthma susceptibility loci is 17q12-17q21.1, but the relationship between this locus and adult asthma is unclear. Association analysis of 13 single nucleotide polymorphisms (SNPs) and haplotypes from 17q12-17q21.1 was performed in 418 adult patients with asthma and 288 controls from Slovenia. Single SNP analysis revealed only marginal associations with adult asthma for SNPs located in GSDMA, GSDMB, ORMDL3 and ZPBP2 genes, and rs7219080 was the most highly associated. Analyses of asthma phenotypes found no association with atopy or lung function, but rs2305480 and rs8066582 were associated with childhood asthma and rs9916279 was associated with asthma in smokers. Notably, haplotypes consisting of rs9916279, rs8066582, rs1042658, and rs2302777 harbouring PSMD3, CSF3 and MED24 genes were highly associated with asthma. The four most common haplotypes, TCCG, TTTA, CCCA and TTCA, were more frequent in patients with asthma, whereas TTCG, TCCA, TCTA and TTTG were more frequent in controls. Only 3% of asthma patients belonged to haplotypes TTCG, TCCA, TCTA and TTTG compared with nearly one-third (31%) of controls. Associations confirmed that the 17q12-17q21.1 locus harbours a genetic determinant for asthma risk in adults and suggest that in addition to the previously known ORMDL3-GSDM locus, CSF3-PSMD3-MED24 also plays a role in asthma pathogenesis.     

Polymorphisms in the interleukin-4 and interleukin-4 receptor α chain genes confer susceptibility to asthma and atopy in a Caucasian population

BACKGROUND : IL-4 by binding to its receptor (IL-4R) is essential for the development of airway inflammation present in asthma, through the induction of IgE synthesis in B cells and differentiation of T cells to a Th2 phenotype. OBJECTIVE : To investigate the role of four common polymorphisms in the IL-4 (IL4-34CT and IL4-589CT) and IL-4Ralpha chain (IL4RAI50V and IL4RAQ576R) genes in conferring susceptibility to the development of atopy and/or asthma. METHODS : Two polymorphisms in the IL-4 gene promoter, IL4-34CT and IL4-589CT, and two polymorphisms in the IL-4Ralpha chain gene, IL4RAI50V and IL4RAQ576R, have been genotyped using PCR-based methods in 341 asthmatic families and in 184 non-asthmatic adults recruited from the south of England. RESULTS : Case-control analysis did not reveal differences in the distribution of the four polymorphisms between asthmatics and controls. However, the transmission disequilibrium test showed that the IL4-589 T allele was preferentially transmitted to asthmatic children (P=0.036) and that the IL4RAQ576 was preferentially transmitted to children with atopic asthma (P=0.018). Haplotype analysis showed a strong association between the IL4-34T/-589T haplotype and asthma per se (P=0.041), and a strong association between the IL4RA I50/Q576 haplotype and atopic asthma (P=0.006). CONCLUSION : Our data suggest that polymorphisms in the IL-4 and IL-4Ralpha chain genes might play a role both conferring susceptibility to and modulating severity of atopy and asthma.     

中国山东沿海地区汉族男性人群白介素-23受体基因多态性与痛风的易感性研究

目的探讨中国山东省沿海地区汉族男性群体的白细胞介素23受体（IL-23R）基因rs7517847位点G／T的多态性是否与痛风的易感性有关。方法选取202例痛风患者和346例健康对照者,检测中国汉族男性群体的IL-23受体内含子区rs7517847位点基因多态性分布,数据经,检验得出其与痛风发病的遗传易感性的关系。结果经,检验,痛风组和对照组中IL-23R基因rs7517847位点GG,GT和1Tr基因型频率（10．4％,49．5％,40．1％;16．2％,49．7％,34．1％;X^2=4．305,P〉0．05）与等位基因频率G和T（35．1％,41％;64．9％,59％;X^2=3．727,P〉0．05）均无统计学意义。IL-23R基因rs7517847位点G／T基因多态性与痛风病的危险因素无显著性关联。结论尚不能认为中国沿海地区汉族男性人群中IL-23R内含子区rs7517847位点基因多态性与痛风有关联性。     

中国汉族人群TIRAP基因编码区多态性与结核病易感性的相关性研究

目的 筛选中国汉族人群Toll/白细胞介素1受体结构域衔接蛋白(TIRAP)基因编码区多态性位点,并分析其与结核病易感性的相关性.方法 在小样本中测序筛选TIRAP基因编码区多态性位点,再用连接酶特异检测技术在大样本中进行单核苷酸多态性(SNP)分型,并通过统计学方法分析基因多态性与结核病易感性的相关性.结果 共筛选到4个TIRAP基因编码区多态性位点.G394A位点在结核病病人中的突变频率高于健康人,但是该位点等位基因频率在两组人群中的差异没有统计学意义(P>0.05).G164A位点跟结核病病情有关,复治病人与健康人该位点等位基因差异具有统计学意义(P<0.05),同时肺部形成空洞病人与菌阳病人突变率均比健康人要低.结论 TIRAP 基因编码区多态性可能是中国汉族人群结核病发生发展的危险因素.

Abstract：

Objective To detect specific polymorphisms in Toll-interleukin 1 receptor domain containing adaptor protein(TIRAP) coding region for Chinese Han population, and verify whether they are associated with susceptibility to tuberculosis. Methods Search TIRAP polymorphisms by sequencing in small sample; detect single nucleotide polymorphism(SNP) by ligase detection reaction technique in large sample; analyze whether polymorphisms are related to tuberculosis by statistic methods. Results Four polymorphisms were present in the TIRAP coding region. 394A had higher frequencies in the tuberculosis(TB)group than the control. But allelic and genotypic analysis showed that there were no significant difference in statistic between TB patients and controls(P>0.05). The SNP G164A mutation related with TB patient's condition. Comparing to controls, retreatment patients' allelic frequencies had significant difference in statistic(P<0.05), sputum positive patients and lung cavitation patients had lower 164A frequencies. Conclusion TIRAP coding region polymorphisms may be risk factors for TB occurrence and development in Chinese Han population.     

Polymorphisms of CYP1A1 and GSTM1 genes and susceptibility to oral cancer

PURPOSE: Oral cancer is the fifth most common form of cancer in the world and comprises 6.5% of all cancer deaths. Since one of the major risk factors for oral cancer is tobacco use, we hypothesized that polymorphic genes coding for tobacco carcinogen-metabolizing enzymes may play a role in oral cancer susceptibility. MATERIALS AND METHODS: To investigate the association between polymorphisms of the CYP1A1 and GSTM1 genes and risks for oral squamous cell carcinoma (OSCC) in the Korean population, the prevalence of the CYP1A1 Mspl and GSTM1 null polymorphisms were examined in 72 patients with histologically confirmed primary OSCC, as well as in 221 healthy control subjects. RESULTS: A significant risk increase for oral cancer was observed among subjects with the homozygous CYP1A1 (m2/m2) genotype (OR=3.8, 95% CI=1.9-7.7), but not the GSTM1 null genotype (OR=0.7, 95% CI=0.4-1.3). Risk for oral cancer was significantly increased in subjects with the homozygous CYP1A1 (m2/m2)genotype, regardless of smoking history (smokers; OR=4.4; 95% CI=1.2-16.3; non- smokers OR=4.9; 95% CI=1.9-12.5). Using the potentially most protective genotype GSTM1 (+)/CYP1A1 [(m1/m1)+ (m1/m2)] as the reference group, an increased risk for oral cancer was observed among subjects with the GSTM1 (+)/ CYP1A1 (m2/m2) (OR= 2.0, 95% CI=0.8-5.2), and GSTM1 (-)/ CYP1A1 (m2/m2) (OR=4.9, 95% CI=1.5-15.5) genotypes (p < 0.009, (chi2 trend test). CONCLUSION: Our results suggest that individuals with a genotype of CYP1A1 (m2/m2) and GSTM1 (-) are highly susceptible for OSCC and that the CYP1A1 (m2/m2) genotype is closely associated with increased risk of OSCC in Koreans.     

Polymorphisms in the promoter regions of FAS and FASL genes as candidate genetic factors conferring susceptibility to endometriosis

Although the pathophysiological mechanisms leading to endometriosis remain unknown, several hypothesis have been proposed, including a dysregulation of the normal apoptotic process which takes place in the endometrium. One of the apoptotic pathways playing a crucial role in the programmed cell death within the endometrium is the Fas-FasL system. In this study we have performed a case-control analysis in order to evaluate three polymorphisms located within FAS (-1377G>A and -670A>G) and FASL (-843C>T) genes, as susceptibility factors for endometriosis. We have analysed a series of women with endometriosis compared respectively to a group of women without symptoms of the disease, and to a group of confirmed unaffected women. The genotyping of the three variants was carried out by Fluorescence Resonance Energy Transfer (FRET) technology, and statistical analysis was performed using chi2 test with Yates correction. Our results show that the differences in the distribution of the polymorphic variants were not statistically significant when the group of patients was compared to the other groups. Thus, it seems to indicate that the variants here analysed are not involved in the pathogenesis of the disease in our population. However this does not let us to completely exclude such genes as potential candidates for the disease. A complete genetic analysis of the genes involved in the intricate regulatory system of the apoptosis may lead to the identification of susceptibility factors for the disease and a better understanding of its etiology.     

The effect of IL-10 genetic variation and interleukin 10 serum levels on Crohn's disease susceptibility in a New Zealand population

Interleukin (IL)-10 has important effects in immunoregulation and inflammation, and previous studies have provided evidence for the involvement of IL-10 in the pathogenesis of Crohn's disease (CD). In this study, we investigated whether genetic variants of the IL-10 gene were associated with CD in a New Zealand population. Three single nucleotide polymorphisms (SNPs) in the promoter region of IL-10 (rs1800871, rs1800872, and rs1800896) and a flanking SNP, rs3024505, were genotyped in a well-characterized New Zealand dataset consisting of 342 CD cases and 610 controls. Furthermore, we measured serum IL-10 levels in a number of the CD patients and controls and examined whether a relationship existed between these polymorphisms and serum IL-10 levels. We demonstrated an association with CD for SNPs rs3024505 and rs1800896, and phenotypic analysis indicated an association of rs3024505 with an early age at first diagnosis, stricturing CD behavior, and requirement for bowel resection. We also observed that IL-10 concentration was significantly higher in CD patients than in the controls and that the T allele of rs1800896, the A allele of rs1800871, and the T allele of rs1800872 were associated with increased serum IL-10 levels.     

Polymorphisms in one-carbon metabolism pathway genes and risk for bladder cancer in a Tunisian population

Cigarette smoking is the most important risk factor for bladder cancer. Moreover, epidemiologic studies have implicated several genetic variations interfering with methyl group metabolisms in susceptibility for a variety of cancers. Examples of these variations can be found in genes of the folate metabolic pathway, which is crucial in the provision of methyl groups for DNA, RNA, and protein methylation, as well as in purine and pyrimidine synthesis. We conducted a case–control study to examine the relationship between the methylenetetrahydrofolate reductase (MTHFR C677 T and MTHFR A1298C), methionine synthase (5-methyltetrahydrofolate-homocysteine methyltransferase, MTR A2756 G), methionine synthase reductase (5-methyltetrahydrofolate-homocysteine methyltransferase reductase, MTRR A66 G and MTRR C524 T), and thymidylate synthase (TYMS 2R→3R and G/C) genotypes and the risk for bladder cancer in a Tunisian population. The isolated MTHFR 677*T, MTRR 66*G and MTRR 524*T variants did not appear to influence bladder cancer susceptibility. The 3R*C/3R*C genotype for the TYMS gene appears to be a protective factor against bladder cancer development (P=0.0001; OR=0.12; 95% CI=0.03–0.40). However, patients heterozygous for MTHFR A1298C or MTR A2756 G genotypes have 1.62- and 2.13-fold higher risk, respectively, of developing bladder cancer. Moreover, the combined study of MTHFR 1298*C and MTR 2756*G variants with either or both MTRR 66GG and TYMS 3R*G/3R*G genotypes suggests a cumulative effect. Finally, this study evidenced that interaction between gene variations involved in folate metabolism and risk of bladder cancer increased dramatically among smokers.     

Polymorphisms for microsomal epoxide hydrolase and genetic susceptibility to COPD

Although smoking is the major causal factor in the development of chronic obstructive pulmonary disease (COPD), only 10-20% of chronic heavy cigarette smokers develop symptomatic COPD, which suggests the presence of genetic susceptibility. The human microsomal epoxide hydrolase (EH) is a metabolizing enzyme which involves the process of numerous reactive epoxide intermediates and contains polymorphic alleles which are associated with altered EH activity and may be linked to increased risk for COPD. To determine whether the EH polymorphisms contributed to increased risk for COPD, prevalence of the EH codons 113 and 139 polymorphisms were compared between COPD patients and controls by a PCR-RFLP analysis using genomic DNA isolated from 131 COPD patients and 262 individually matched controls by age (+/-5 years) among Caucasians with 2:1 ratio. Significantly increased risk for COPD was observed for subjects with the EH(113His/His) genotypes (OR=2.4, 95% CI=1.1-5.1). These results were consistent with the fact that a significant trend towards increased risk was observed with predicted less protective EH codon 113 genotypes (p=0.03, trend test). A similar association was not observed for EH codon 139 polymorphism. As expected, a significant correlation between smoking dose and severity of COPD was observed (p<0.001). These results suggest that EH codon 113 polymorphism may modify risk for COPD.     

The influence of T cell receptor and cytokine genes on sarcoidosis susceptibility in African Americans.

The pathogenesis of sarcoidosis, a multisystem granulomatous disorder, is mediated through immunoregulatory pathways. While sarcoidosis clusters in families, inherited risk factors remain undefined. In search of possible sarcoidosis susceptibility genes, we examined anonymous polymorphic genetic markers tightly linked to six different candidate gene regions on chromosomes 2q13, 5q31, 6p23-25, 7p14-15, 14q11 and 22q11. These candidate regions contain T cell receptor, interleukin (IL) and interferon regulatory factor (IRF) genes. Our study population consisted of 105 African-American sarcoidosis cases and 95 unrelated healthy controls. The allelic frequency distribution of two out of the six markers, IL-1 alpha marker (p = 0.010) on 2q13 and the F13A marker (p = 0.0006) on 6p23-25, was statistically significantly different in cases compared with controls. The two alleles most strongly associated with sarcoidosis were IL-1 alpha*137 (Odds Ratio (OR) = 2.60; 95% confidence interval (CI) = 1.36-4.98) and F13A*188 (OR = 2.42; 95% CI = 1.37-4.30). Individuals that had both of these alleles were at a six-fold increased risk for sarcoidosis (OR = 6.19; 95% CI = 2.54-15.10). Restricting the analysis to cases with at least one first or second-degree relative affected with sarcoidosis increased the OR to 15.38. IL-1 levels are elevated in sarcoidosis and the F13A marker is tightly linked to a gene that codes for a newly identified interferon regulatory factor protein (IRF-4), which is thought to play a role in T cell effector functions. Our results suggest genetic susceptibility to sarcoidosis may be conferred by more than one immune-related gene that act synergistically on disease risk.