Fas ligand gene polymorphisms are not associated with Hashimoto's thyroiditis and Graves' disease

Fas/FasL gene polymorphism in patients with Hashimoto's thyroiditis in Turkish population

OBJECTIVE

Hashimoto's disease is a polygenic disorder with complex etiopathogenesis. Apoptosis is proposed as one of its mechanisms. The Fas/Fas ligand cascade represents a major pathway initiating apoptosis. This study aims to evaluate the influence of Fas and FasL gene polymorphism in Hashimoto's thyroiditis in Turkish population.

MATERIALS AND METHODS

A total of 112 patients with Hashimoto's thyroiditis and 112 cases of healthy control people were included in this study. The evaluation of genotype for Fas -670 A/G and FasL 843 C/T gene polymorphism was performed by using PCR-RFLP method.

RESULTS

The FAS genotype and gene allele frequency distribution did differ between the control group (AA 36.6 %, AG 50.0 %, GG 13.4 %, A 61.6 %, G 38.4 %) and the Hashimoto's thyroiditis patients (AA 21.4 %, AG 50.9 %, GG 27.7 %, A 46.9 %, G 53.1 %) (p < 0.01). The evaluation of FasL genotype and gene allele frequency did not show statistically significant difference between the patient group (CC 27.7 %, CT 45.5 %, TT 26.8 %, C 50.4 %, T 49.6 %) and control group (CC 33.9 %, CT 44.6 %, TT 21,4 %, C 56.3 %, T 43.8 %) (p > 0.05).

CONCLUSIONS

Gene polymorphism of Fas and G allele frequency may play a role in the regulation of apoptosis in thyroid autoimmune disorders. There is a need for further studies to clarify the genetic role of apoptosis in HT.

Apoptosis-related Fas and FasL gene polymorphisms' associations with knee osteoarthritis

To investigate the associations between Fas and FasL gene polymorphisms and susceptibility to knee osteoarthritis. Genomic DNA was obtained from 146 patients with knee osteoarthritis and 102 healthy controls. Genotype distributions and allelic frequencies of four polymorphisms of Fas (-670 G>A rs1800682, -1377 G>A rs2234767) and FasL (IVS2nt-124 A>G rs5030772, -844 T>C rs763110) genes were compared between the groups. Thereafter, this association was investigated between patients and controls of the same sex. There were significant differences between patients with knee osteoarthritis and controls regarding the genotype distributions and allelic frequencies of Fas-1377 G>A polymorphism (P = 0.0001 and P = 0.005, respectively). The Fas-1377 GG genotype and G allele were significantly more frequent in patients with knee osteoarthritis than in controls. Genotype distributions and allelic frequencies of Fas-670 G>A, FasL-844 T>C, and FasL IVS2nt-124 A>G polymorphisms did not differ between the groups (P > 0.05). However, there were no significant differences between patients and controls of the same sex (P > 0.05). These findings suggest that the Fas-1377 G>A polymorphism in the Fas gene related with apoptosis may contribute to susceptibility to knee osteoarthritis in the Turkish population. There is a need for further studies to evaluate the role of apoptosis in large cohorts.

Single-nucleotide gene polymorphisms involving cell death pathways: a study of Chinese patients with lumbar disc herniation

OBJECTIVE

To evaluate the effect of polymorphisms of death pathway genes FAS and FASL on the risk of developing lumbar disc herniation (LDH) in a Northern Chinese population.

BACKGROUND DATA

The FAS receptor-ligand system plays a key role to regulate apoptosis of cell. There is evidence that the apoptosis-mediated FAS receptor-ligand system is involved in the pathogenesis of disc degeneration. Some research considered single-nucleotide polymorphisms of FAS-1377G/A, FAS-670A/G, FASL-844T/C, and FASL INV2nt-124A/G may increase the risk of developing cancer. We therefore assess these four single-nucleotide polymorphisms as candidate susceptibility for LDH.

METHODS

A total of 475 patients with LDH and 533 control subjects were selected. Genotypes were determined by polymerase chain reaction-based restriction fragment length polymorphism and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Associations with the risk of LDH were estimated by logistic regression model.

RESULTS

Significant differences were found in genotypic distributions between cases and controls for FASL-844T/C, but not for other three polymorphisms. When compared with CC genotype, subjects with the TT genotype had a higher risk to develop LDH (odds ratio = 3.12; 95% confidence interval: 1.73-5.40). Moreover, an association was found between this genotype of FASL-844TT and more severe grades of disc degeneration. We observed statistically significant interactions between polymorphisms of FASL-844T/C and lumbar load, tobacco smoking, and age.

CONCLUSION

Genetic polymorphisms of FASL-844T/C may be associated with an increased risk of developing disc degeneration and LDH.

Fas, Fas Ligand, and vitamin D Receptor FokI gene polymorphisms in patients with type 1 diabetes mellitus in the Aegean region of Turkey

OBJECTIVE

Several gene polymorphisms have been reported to be associated with the risk of developing type 1 diabetes. Among them, the human leukocyte antigen locus is the strongest genetic determinant. To identify additional genetic markers, we aimed to evaluate the relationship between the Fas, Fas ligand (FasL), and vitamin D receptor (VDR) FokI gene polymorphisms and the susceptibility to type 1 diabetes in the Aegean region of Turkey.

MATERIALS AND METHODS

Eighty-five patients with type 1 diabetes and 80 healthy controls were included in this study. The Fas -670A/G, FasL -843C/T, and VDR FokI gene polymorphisms were evaluated using the polymerase chain reaction-restriction fragment length polymorphism method.

RESULTS

The evaluation of the Fas genotype and the gene allele frequency did not show statistically significant differences between the patient and control group. Distribution of the FasL genotype differed significantly between patients and controls. The distribution of the VDR FokI genotype and allele frequencies differed significantly between the patients and controls. Individuals with type 1 diabetes presented less commonly with the FokI f allele.

CONCLUSIONS

Our findings suggest that the FasL -843C/T and VDR FokI gene polymorphisms are associated with type 1 diabetes in the Agean region of Turkey; however, the Fas -670A/G gene polymorphism is not.

Evaluation of apoptosis-related gene Fas (CD95) and FasL (CD178) polymorphisms in Iranian rheumatoid arthritis patients

Apoptosis signals are essential for establishing homeostasis and adequate immune response. Dysregulation of apoptosis-related genes in the immune system, which could be due to gene polymorphisms, conduct to autoimmune diseases including rheumatoid arthritis. In the current study, the apoptosis-related gene Fas_-670A>G, FasL_844C>T, and FasLIVS2nt_124A>G polymorphisms were genotyped in 120 Iranian patients with rheumatoid arthritis (RA) and 112 unrelated healthy controls using PCR-RFLP method. Among the 120 RA patients being heterozygous in the promoter region of Fas_-670A/G (OR 1.42,CI 0.92-1.52, P = 0.18) and FasL_-844C/T (OR 1.42, CI 0.92-1.52, P = 0.18) and homozygous in the minor allele for FasLIVS2nt_124G/G (OR 1.43, CI 0.76-1.81, P = 0.7), the frequency of these polymorphisms is higher in the cases than in controls and the elevated risk of RA were observed when the patient compared with controls, although this is not statistically significant.

Evaluation of apoptosis-related genes: Fas (CD94), FasL (CD178) and TRAIL polymorphisms in Iranian multiple sclerosis patients

Multiple sclerosis (MS) is a central nervous system (CNS) demyelinating disease characterized by a relapsing-remitting course leading to progressive disability. Given the critical role of apoptosis-related genes in the maintenance of homeostasis in the immune privilege sites, mutations in these genes have a profound effect on occurring autoimmune diseases such as multiple sclerosis. In the current study, polymorphisms in the apoptosis-related genes: Fas _-670 A>G, FasL _-844C>T, FasLIVS2nt _124 A>G and TRAIL_1595C>T were analyzed in 107 Iranian patients suffering from MS and 112 unrelated healthy controls using PCR-RFLP method. Our results demonstrated that among Iranian patients with MS and controls being homozygous in Fas_670A/A, G/G and FasL_-844C/C, TT in the promoter region and homozygocity in the minor allele for FasLIVS2nt_124G/G and TRAIL_1595C/C, polymorphisms were not associated with the MS risk in Iranian patients when compared with normal controls. However, the Fas _-670G/G genotype had a borderline significantly increased frequency with secondary progressive MS type (X(2)=5.8, P=0.05). In conclusion, no statistical association was found between the Fas, FasL and TRAIL polymorphisms and the risk of MS in Iranian patients.

Single Nucleotide Polymorphisms in Selected Apoptotic Genes and BPDE-Induced Apoptotic Capacity in Apparently Normal Primary Lymphocytes: A Genotype-Phenotype Correlation Analysis

Apoptotic capacity (AC) in primary lymphocytes may be a marker for cancer susceptibility, and functional single nucleotide polymorphisms (SNPs) in genes involved in apoptotic pathways may modulate cellular AC in response to DNA damage. To further examine the correlation between apoptotic genotypes and phenotype, we genotyped 14 published SNPs in 11 apoptosis-related genes (i.e., p53, Bcl-2, BAX, CASP9, DR4, Fas, FasL, CASP8, CASP10, CASP3, and CASP7) and assessed the AC in response to benzo[a]pyrene-7,8-9,10-diol epoxide (BPDE) in cultured primary lymphocytes from 172 cancer-free subjects. We found that among these 14 SNPs, R72P, intron 3 16-bp del/ins, and intron 6 G>A in p53, -938C>A in Bcl-2, and I522L in CASP10 were significant predictors of the BPDE-induced lymphocytic AC in single-locus analysis. In the combined analysis of the three p53 variants, we found that the individuals with the diplotypes carrying 0-1 copy of the common p53 R-del-G haplotype had higher AC values compared to other genotypes. Although the study size may not have the statistical power to detect the role of other SNPs in AC, our findings suggest that some SNPs in genes involved in the intrinsic apoptotic pathway may modulate lymphocytic AC in response to BPDE exposure in the general population. Larger studies are needed to validate these findings for further studying individual susceptibility to cancer and other apoptosis-related diseases.

Functional polymorphisms of the FAS gene associated with risk of vitiligo in Chinese populations: a case-control analysis

The FAS/FASLG system plays a key role in regulating apoptosis. Previous findings have shown that CD4-dependent destruction of melanocytes is partially inhibited by blocking FAS-FASLG interactions in autoimmune vitiligo. Functional polymorphisms of the FAS and FASLG genes can alter their transcriptional activities. In a hospital-based case-control study of 750 vitiligo patients and 756 controls, we genotyped the FAS-1377 G>A, FAS-670 A>G, and FASLG-844 T>C polymorphisms and assessed their association with the risk of vitiligo. We found that a significantly increased risk of vitiligo was associated with the FAS-1377 AA genotype (adjusted odds ratio (OR), 1.49; 95% confidence interval (CI), 1.07-2.08) and the FAS-1377 AG genotype (adjusted OR, 1.31; 95% CI, 1.05-1.63) when compared with the FAS-1377 GG genotype. However, no evident risk was associated with FAS-670 G>A genotypes. In the combined analysis of the two variant alleles of FAS, genotypes with 3 to 4 risk alleles were associated with an increased risk of vitiligo compared with those having 0-2 variants (adjusted OR, 2.87; 95% CI, 1.90-4.32). In conclusion, genetic variants in the FAS gene may affect the risk of vitiligo in Chinese populations.

Dominant inhibition of Fas ligand-mediated apoptosis due to a heterozygous mutation associated with autoimmune lymphoproliferative syndrome (ALPS) Type Ib

Background:

Autoimmune lymphoproliferative syndrome (ALPS) is a disorder of lymphocyte homeostasis and immunological tolerance due primarily to genetic defects in Fas (CD95/APO-1; TNFRSF6), a cell surface receptor that regulates apoptosis and its signaling apparatus.

Methods:

Fas ligand gene mutations from ALPS patients were identified through cDNA and genomic DNA sequencing. Molecular and biochemical assessment of these mutant Fas ligand proteins were carried out by expressing the mutant FasL cDNA in mammalian cells and analysis its effects on Fas-mediated programmed cell death.

Results:

We found an ALPS patient that harbored a heterozygous A530G mutation in the FasL gene that replaced Arg with Gly at position 156 in the protein's extracellular Fas-binding region. This produced a dominant-interfering FasL protein that bound to the wild-type FasL protein and prevented it from effectively inducing apoptosis.

Conclusion:

Our data explain how a naturally occurring heterozygous human FasL mutation can dominantly interfere with normal FasL apoptotic function and lead to an ALPS phenotype, designated Type Ib.

Interleukin-1-beta gene, but not the interleukin-1 receptor antagonist gene, is associated with Graves' disease

Interleukin-1 (IL-1) is considered to be involved in the pathogenesis of Graves' disease. The aim of this study was to test whether the IL-1-beta gene promoter region and exon 5 and IL-1 receptor antagonist (IL-1Ra) gene intron 2 polymorphisms could be useful genetic markers for susceptibility to Graves' disease. A normal control group of 163 healthy people and another group of 95 patients with Graves' disease were examined. Polymerase chain reaction (PCR) was used to analyze the variable number of tandem repeats (VNTRs) at intron 2 of the IL-1Ra gene for the polymorphism. PCR-based restriction analysis was done for the IL-1-beta gene polymorphisms of the promoter region and exon 5 using endonucleases AvaI and TaqI, respectively. We found significantly increased frequencies of the C/C homozygous genotype (chi(2) test, P=0.038; odds ratio (OR)=2.558, 95% confidence interval (CI)=1.205-5.430) and the C allele (chi(2) test, P=0.011; OR=1.589, 95% CI=1.094-2.309) in the IL-1-beta gene promoter (-511 C/T polymorphism) in Graves' disease patients compared to normal controls. There were no significant differences in polymorphisms of IL-1-beta gene exon 5 and IL-1Ra gene intron 2 between the patient and normal control groups. A subgroup analysis also demonstrated no association between the severity of the disease and any polymorphism of IL-1-related genes. We suggest that the IL-1-beta gene promoter polymorphism can be used as a genetic marker for susceptibility to Graves' disease. It is worthwhile to study the cytokine genes further because of the association between cytokines and Graves' disease.

Fas/Fas ligand gene polymorphism in patients with papillary thyroid cancer in the Turkish population

OBJECTIVE

Fas ligand (FasL) is an apoptotic agent and a member of tumor necrosis factor (TNF) family. FasL exists in cytotoxic T lymphocyte (CTL) and natural killer (NK) cells, and it is increased in tumor cell membrane. On the contrary, CTL and NK are bound to Fas on the surfaces of cell membrane; this triggers apoptosis in cytotoxic cells and leads to their death. This system plays an important role in eliminating viral infections and cancer cells. Malfunction of this system results in the development and spread of the malignancy. This study aims at evaluating the influence of Fas and FasL gene polymorphism in papillary thyroid cancer (PTC) in the Turkish population.

RESEARCH DESIGN AND METHODS

Forty-five patients with PTC and 100 healthy controls were included in this study. The diagnosis of PTC was confirmed by histopathologic examination after surgery. The evaluation of genotype for Fas 670 A/G and FasL 843 C/T gene polymorphism was performed using the PCR-restriction fragment length polymorphism (RFLP) method.

RESULTS

The evaluation of Fas/FasL genotype and gene allele frequency did not show statistically significant differences between the patient and control group (p>0.05). In addition, the univariate analysis did not reveal a statistically significant relationship between the size of the nodule and the Fas/FasL gene polymorphism in patients with PTC.

CONCLUSIONS

As in other types of malignancy, genetic factors in the pathogenesis of PTC may also show changes in different populations. Fas/FasL gene polymorphysms are possible that different mechanisms function in apoptosis balance in PTC development.

Polymorphisms of FAS and FAS Ligand Genes Involved in the Death Pathway and Risk and Progression of Squamous Cell Carcinoma of the Head and Neck

PURPOSE

Alteration of the FAS/FAS ligand (FASLG) pathway regulating cell death may lead to cancer development, but the effects of functional promoter polymorphisms of the FAS and FASLG genes on risk of squamous cell carcinoma of the head and neck (SCCHN) are unknown.

DESIGN

We genotyped the FAS -1377 G>A, FAS -670 A>G, FASLG -844 C>T, and FASLG IVS2nt -124 A>G polymorphisms in 721 case patients with SCCHN and 1,234 cancer-free non-Hispanic White control subjects frequency-matched by age and sex. Multivariate logistic regression was used to assess the adjusted odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Compared with the FAS -1377 GG and -670 AA genotypes, the FAS -1377 AA and -670 (GG+AG) genotypes were associated with an increased risk of SCCHN (OR, 2.23; 95% CI, 1.07-4.64 and OR, 1.24; 95% CI, 1.01-1.52, respectively), whereas no risk of SCCHN was associated with any of the FASLG genotypes. When we used the combined FAS -1377 (GG+AG)/-670 AA genotypes as the reference, we found that the individuals carrying the FAS -1377 AA/-670 (GG+AG) had the highest risk (OR, 2.69; 95% CI, 1.24-5.83), whereas individuals carrying genotypes other than FAS -1377 (GG+AG)/-670 AA had a higher risk of SCCHN (OR, 1.24; 95% CI, 1.01-1.52). Furthermore, the elevated risk was particularly evident for pharyngeal cancer with the larger tumors without regional lymph metastasis (OR, 1.77; 95% CI, 1.07-2.94).

CONCLUSIONS

The FAS (but not FASLG) polymorphisms seem to contribute to risk of developing SCCHN, particularly the pharyngeal cancer in non-Hispanic Whites. However, potential selection bias warrants future population-based studies to verify the findings.

Polymorphisms of the FAS and FAS ligand genes associated with risk of cutaneous malignant melanoma

The FAS/FAS ligand (FASLG) system has a key role in regulating cell growth and thus tumorigenesis. Functional promoter polymorphisms of the FAS and FASLG genes alter the transcriptional activities, but no published study has investigated the role of these polymorphisms in the etiology of cutaneous malignant melanoma (CMM). In a hospital-based, case-control study of 602 non-Hispanic white CMM patients and 603 cancer-free age- and sex-matched control subjects, we genotyped FAS-1377G>A, FAS-670A>G, FASLG-844T>C and FASLG-IVS2nt-124G>A polymorphisms and assessed their respective associations with CMM risk. We found that an increased risk of CMM was associated with the FAS-1377GG [adjusted odds ratio (OR)=1.32; 95% confidence interval (CI)=1.00-1.75 for -1377GG] and -670AA (adjusted OR=1.28; 95% CI=1.00-1.65 for -670AA) genotypes compared to the -1377AA/AG and -670AG/GG genotypes, respectively; an increased risk of CMM was associated with the FASLG-IVS2nt-124AG+GG (OR=1.54; 95% CI=1.18-2.01) genotype compared to the AA genotype, but no evident risk was associated with any of the FAS-844T>C genotypes. In the combined analysis of these four variant alleles, we found that, compared to those having 0-3 variants, those having 4-8 variant alleles had a significantly increased risk for CMM (OR=1.38; 95% CI=1.10-1.73), and this risk was more pronounced in subgroups of old (>50 years) males, and those who were at low risk of sunlight-induced CMM, except for having fair skin colour, moles, dysplastic nevi and a family history of cancer. In conclusion, genetic variants in the FAS and FASLG genes may contribute to the etiology of CMM in the general population, particularly in those with a low risk of sunlight-induced CMM.

Functional polymorphisms in the promoter regions of the FAS and FAS ligand genes and risk of bladder cancer in south China: a case–control analysis

BACKGROUND

FAS and FASLG together initiate apoptosis, which prevents tumor development. FAS and FASLG polymorphisms in the promoter regions can alter the transcriptional activities and thus alter risk of cancer. We hypothesized that the FAS -1377G>A, -670A>G, and FASLG -844T>C polymorphisms are associated with risk of bladder cancer.

METHODS

In a hospital-based case-control study of 216 case patients with newly diagnosed bladder transitional cell carcinoma and 252 cancer-free controls frequency-matched by age and sex, we genotyped polymorphisms using PCR-restriction fragment length polymorphism.

RESULTS

We found a statistically significantly increased risk of bladder cancer associated with the FASLG -844CC genotype [adjusted OR=1.51; 95% CI 1.03-2.23] compared with -844 (CT+TT). Consistently, the FAS haplotype genotypes with 2-4 variant (risk) alleles (-1377A and -670A) were associated with an increased risk of bladder cancer compared to 0-1 variants (OR=2.14; 95% CI 1.10-4.16). Furthermore, when we evaluated these three polymorphisms together, we found that the combined genotypes with 4-6 variant (risk) alleles (-1377A, -670A, and -844C) were associated with an increased risk of bladder cancer (OR=1.58; 95% CI 1.07-2.34) compared to 1-3 variants, and this increased risk was more pronounced among subgroups of aged >50 years (OR=1.70; 95% CI 1.11-2.61) and smokers (OR=1.88; 95% CI 1.06-3.32).

CONCLUSIONS

FAS and FASLG polymorphisms appear to jointly contribute to risk of bladder cancer in this southern Chinese population. Larger studies are needed to verify these findings.

Study of Fas (CD95) and FasL (CD178) polymorphisms in liver transplant recipients

The Fas receptor is capable of transducing apoptotic cell death upon interaction with their ligand (FasL). Recent studies suggest that the Fas/FasL system is involved both in graft rejection and in transplantation tolerance. In this study, we analyzed the effect of Fas and FasL polymorphisms in liver allograft outcome. Fas and FasL polymorphisms were analyzed in 151 primary liver graft recipients. The Fas (-670 A/G) and the FasL (IVS2nt -124 A/G and IVS3nt 169 T/delT) polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism. Fas -1377 G/A polymorphism was determined by allele-specific amplification. Fas and FasL polymorphisms were not associated with acute and chronic rejection in liver transplant. In contrast, those recipients bearing the AA -670 Fas genotype showed significantly lower graft survival rate (S = 40%) than those bearing the GA genotype (S = 63.1%). These differences were detected from the first year post-transplant. Multivariate analysis confirmed that the AA genotype increased the risk of liver graft loss. This work suggests for the first time a possible harmful effect of Fas -670 AA genotype on liver graft survival, whereas the Fas and FasL polymorphisms are not associated with acute or chronic rejection in liver graft recipients.

Polymorphisms in apoptosis genes predict response to infliximab therapy in luminal and fistulizing Crohn's disease

BACKGROUND

Infliximab treatment is effective in 70-80% of patients with refractory luminal and fistulizing Crohn's disease. The effect of infliximab is ascribed to induction of apoptosis.

AIM

To study whether polymorphisms in apoptosis genes predict the response to infliximab and whether they interact with clinical predictors.

METHODS

Cohort of 287 consecutive patients treated with infliximab for refractory luminal (n = 204) or fistulizing (n = 83) Crohn's disease was genotyped for 21 polymorphisms in apoptosis genes. Short-term clinical response was assessed at week 4 (luminal Crohn's disease) or 10 (fistulizing Crohn's disease) after the first infliximab infusion.

RESULTS

The response rate was 69% in luminal and 80% in fistulizing Crohn's disease. In luminal Crohn's disease, two genetic predictors were identified: (i) patients with the Fas ligand -843 CC/CT genotype (n = 135) responded in 75%, with the TT genotype (n = 21) in 38% only (P = 0.002; OR = 0.11; 95% CI: 0.08-0.56). (ii) Patients with the caspase-9 93 TT (n = 9) genotype all responded, in contrast with 67% (n = 147) with the CC and CT genotype (P = 0.04; OR = 1.50; 95% CI: 1.34-1.68). Concomitant azathioprine/mercaptopurine therapy overcame the effect of unfavourable genotypes. In the fistulizing Crohn's disease cohort, the same Fas ligand -843 CC/CT genotype was the only predictor of response (P = 0.002; OR = 1.66; 95% CI: 1.21-2.29), interacting with caspase-9 93 polymorphism but not with azathioprine/mercaptopurine.

CONCLUSION

We observed that polymorphisms in FasL/Fas system and caspase-9 influence the response to infliximab in luminal and fistulizing Crohn's disease. The strongest association was seen between the Fas ligand -843 TT genotype and non-response. Concomitant mercaptopurine/azathioprine therapy, however, was able to overcome the effect of unfavourable genotypes in luminal disease.

Immunogenetics of Hashimoto's thyroiditis

Hashimoto's thyroiditis (HT) is an organ-specific T-cell mediated disease. It is a complex disease, with a strong genetic component. To date, significant progress has been made towards the identification and functional characterization of HT susceptibility genes. In this review, we will summarize the recent advances in our understanding of the genetic input to the pathogenesis of HT.

The −844C/T polymorphism in the Fas ligand promoter associates with Taiwanese SLE

FasL expression is critical in T-cell activation-induced apoptosis, which is involved in lupus pathogenesis. This study identified two SNPs in the FasL promoter regions from -1145 to -45 by genomic DNA sequencing. The -844C/T polymorphism was previously described by its location in and affect on the CCAAT/enhancer-binding protein beta (C/EBPB beta)-binding site and the other (-1094A/C, a novel polymorphism) was located at the NF-kappaB transcription-binding site. FasL gene promoter polymorphisms were genotyped in 260 systemic lupus erythematosus (SLE) patients and 280 healthy controls using MassArray matrix-assisted laser desorption ionization-time-of-flight (MALDI-TOF) mass spectrometry. The distribution of FasL promoter -844C/C genotype, predominant in Taiwanese, was skewed in Taiwanese SLE patients (odds ratio: 1.53; P-value=0.014). FasL promoter -844C/T polymorphism genotype distributions of Taiwanese, African Americans, and Caucasians differed. Moreover, no particular clinical association of -844C/T and -1094A/C polymorphisms with SLE was found in patients in Taiwan. This study confirmed that -844C/C genotype is associated with lupus susceptibility. The -1094A/C polymorphism is not significantly associated with lupus disease susceptibility, albeit the role of NF-kappaB pathway in FasL promoter activation remains unclear. Fas/FasL pathway may contribute to SLE polygenic disease entity.