Association of FAM167A-BLK rs2736340 Polymorphism with Susceptibility to Autoimmune Diseases: A Meta-Analysis

Objective: The purpose of this study is to evaluate the correlation between family with sequence similarity 167A-B lymphoid tyrosine kinase (FAM167A-BLK) rs2736340 polymorphism and autoimmune diseases.

Methods: Databases including PubMed, EMBASE, Chinese National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature database (CBM) and Chinese database, Wan Fang database were used in searching eligible studies from January 1, 1966 to October 2, 2015. The odds ratios (ORs) and their 95% confidence intervals (CIs) were pooled to estimate the strength of the association.

Results: A total of 25 studies with 30,217 patients and 44,754 controls were included in the meta-analysis. The overall results showed FAM167A-BLK rs2736340 T allele was a risk allele for autoimmune diseases (OR 1.36, 95% CI 1.28–1.44, p < 0.001). In the subgroup by ethnicities, the results suggested T allele was an increased risk in North America, Europe, and Asia (OR 1.33, 95% CI 1.10–1.60, p = 0.004; OR 1.26, 95% CI 1.22–1.31, p < 0.001; and OR 1.46, 95% CI 1.40–1563, p < 0.001, respectively), but not in Africa. Subgroup analysis in different genetic models (recessive, dominant, and additive) revealed significant association between rs2736340 and autoimmune diseases in Asia and North America, but not the recessive model in Europe or Africa, or the additive model in Africa. Stratification analysis by diseases suggested FAM167A-BLK rs2736340 had a positive association with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc) and Kawasaki disease, primary Sjogren’s syndrome (pSS), primary antiphosholipid syndrome (APS), and myositis.

Conclusion: The current meta-analysis suggested that FAM167A-BLK rs2736340 polymorphism is associated with several autoimmune diseases.     

A study on the genetic polymorphisms of CYP3A5 among the Orang Asli in Malaysia using a next generation sequencing platform

Background: CYP3A5 is the predominant sub-family of biotransformation enzymes in the liver and the genetic variations in CYP3A5 are an important determinant of inter-individual and inter-ethnic differences in CYP3A-mediated drug disposition and response.

Aim: This study aims to investigate the genetic polymorphisms of CYP3A5 among the Orang Asli in Peninsular Malaysia using a next generation sequencing platform.

Methods: Genomic DNAs were extracted from blood samples of the three main Orang Asli tribes and whole-genome sequencing was performed.

Results: A total of 61 single nucleotide polymorphisms were identified and all the SNPs were located in introns except rs15524, which is in the 3’UTR, and 11 of these polymorphisms were novel. Two allelic variants and three genotypes were identified in the Orang Asli. The major allelic variant was the non-functional CYP3A5*3 (66.4%). The percentages of Orang Asli with CYP3A5*3/*3 (47.2%) and CYP3A5*1/*3 (38.1%) genotypes are more than twice the percentage of Orang Asli with CYP3A5*1/*1 (14.8%) genotype. Almost half of the Orang Asli harboured CYP3A5 non-expressor genotype (CYP3A5*3/*3).

Conclusions: The predominance of the CYP3A5 non-expressor genotype among the Orang Asli was unravelled and the findings in this study may serve as a guide for the optimisation of pharmacotherapy for the Orang Asli community.     

Distribution of polymorphisms in the CYP2C9 gene and CYP2C19/CYP2C9 haplotypes among Venezuelan populations

Background: Polymorphisms with decreased enzyme activity of their gene products have been reported in region CYP2C with population variations in haplotype structure.

Aim: To estimate the allelic and genotypic frequencies of variants CYP2C9*2 and CYP2C9*3 and of CYP2C9/CYP2C19 haplotypes in Venezuelan populations.

Subjects and methods: Six hundred and thirty-four individuals from nine admixed populations (AP) and the Warao indigenous group were studied. Allelic frequencies, linkage disequilibrium and genetic distances for haplotypes were calculated and compared within Venezuela and with data available in the literature.

Results: Heterogeneity in the distribution of CYP2C9 alleles and CYP2C9/CYP2C19 haplotypes among the AP and the Warao was observed. The joint frequency of haplotypes, with at least one non-functional variant, shows values in AP between 21–41%, while in Warao it reaches 5%. The haplotype that includes the Asian and rare Latin America CYP2C19*3 allele was detected in most AP and in Warao. Pairwise Fst values showed that the Warao was an outlier compared with the AP, while these are closer to European-derived populations. No significant correlation was found between haplotype frequencies and admixture.

Conclusions: These results support the need to understand the distribution of genomic biomarkers related to the metabolism of drugs, for planning national public health strategies.     

Antibodies against Phosphorylcholine among New Guineans Compared to Swedes: An Aspect of the Hygiene/Missing Old Friends Hypothesis

Background: We here study antibodies against phosphorylcholine (anti-PC) which we reported to be inversely associated with atherosclerosis, cardiovascular disease (CVD), and autoimmune conditions. In previous studies, we determined that this inverse association is more pronounced at low levels with high risk and at high levels, with decreased risk. We compare individuals from Kitava, New Guinea (with low risk of these conditions), with Swedish controls.

Methods: We studied a group of 178 individuals from Kitava (age 20–86), and compared those above age 40 (n = 108) with a group of age- and sex-matched individuals from a population based cohort in Sweden (n = 108). Traditional risk factors for CVD and fatty acids were determined. IgM, IgG, and IgA anti-PC were tested by enzyme-linked immunosorbent assay (ELISA).

Results: All anti-PC measures were significantly lower among Swedish controls as compared to Kitavans (p < 0.001), independent of traditional risk factors. Having low levels of anti-PC, defined as below 25th percentile of values among Swedish controls, was associated with this cohort after adjustment for other risk factors (OR 5.7, 95% CI 2.2–14.7 for IgM; OR 31.7, 95% CI 3.9–252 for IgA; and OR 11.1, 95% CI 2.4–51 for IgG).

Conclusions: PC is highly exposed on microorganisms and helminths (common on Kitava) exposing much PC which humans and hominids may have been exposed to for millions of years. We propose that low anti-PC levels in the developed world could be a new aspect of the hygiene hypothesis, generating a pro-inflammatory and pro-atherosclerotic state.     

Genetic Polymorphism (rs329498) in the Pellino-1 Gene as Possible Predisposal Factor for Systemic Lupus Erythematosus in a Chinese Population

Objective: The purpose of this study was to analyze the association of two single nucleotide polymorphisms (SNPs) in Peli-1 gene with systemic lupus erythematosus (SLE) in a Chinese population.

Methods: We conducted a case–control study and a total of 738 SLE patients and 827 healthy controls were finally recruited. Peli-1 rs329498 and rs10496105 polymorphisms were specified from genomic DNA using TaqMan genotyping assay on Fluidigm 192.24 system.

Results: Allele contrast showed the minor allele C was associated with decreased risk for SLE when compared with the A allele (OR = 0.851, 95% CI = 0.737–0.983, p = 0.028). Significant difference was observed in genotype distribution of rs329498 polymorphism between lupus nephritis (LN) patients and non-LN patients (χ² = 8.18, p = 0.017). Furthermore, we also found a decreased frequency of the minor allele C in LN patients (29.2%) than in non-LN patients (37.7%) (χ² = 8.67, p = 0.003). Moreover, a significant difference was also detected under a dominant model with regard to the distribution of genotype frequencies between LN patients and non-LN patients (CC + AC vs. AA: OR = 0.632, 95% CI = 0.451–0.884, p = 0.007). Clinical features analysis showed a significant difference in the distribution of genotypic frequencies between patients with malar rash and patients without this feature (χ² = 6.63, p = 0.036). Unfortunately, we failed to find any significant results between Peli-1 gene rs10496105 and SLE susceptibility.

Conclusions: Our observations suggested that Peli-1 gene polymorphism rs329498 might contribute to SLE susceptibility in Chinese Han Population. Likewise, the rs329498 SNP was also associated with the clinical features LN and malar rash in SLE patients.     

Association between IL-33 Gene Polymorphisms (rs1929992, rs7044343) and Systemic Lupus Erythematosus in a Chinese Han Population

Objective: Interleukin-33 (IL-33) is a member of the IL-1 family, and previous studies found the single-nucleotide polymorphisms (SNPs) in the IL-33 gene was related to susceptibility to autoimmune diseases, including rheumatoid arthritis, ankylosing spondylitis and Behcet’s disease. To date, no study has discussed the potential association between IL-33 gene polymorphisms and systemic lupus erythematosus (SLE).

Methods: We conducted a case-control study including 371 SLE patients and 408 healthy controls to investigate the correlation between the SNPs of IL-33 gene (rs1929992, rs7044343) and SLE in a Chinese Han population.

Results: There was significantly lower expression of allele G for rs1929992 in SLE patients than that in controls (G versus A, P = 0.012, OR = 1.310, 95% CI: 1.060–1.624 after adjustment with sex). Similarly, genotype GG was associated with the susceptibility to SLE as compared with the AA genotype (P = 0.017, OR = 1.714, 95% CI: 1.101–2.669 after adjustment with sex). We also found statistical significance in the dominant model (GG+GA versus AA, P = 0.017, OR = 1.481, 95% CI: 1.074–2.044 after adjustment with sex). However, we found no strong evidence for the association of IL-33 rs7044343 polymorphism with SLE. Moreover, association studies were performed on the relationship between the IL-33 gene polymorphisms and lupus nephritis as well as nine clinical features of SLE, but there was no significant association regarding the distribution of allele and genotype frequencies between SLE patients positive and negative for the presence of sub-phenotypes.

Conclusion: Our findings indicate that IL-33 rs1929992 polymorphism may be a potential biomarker for susceptibility to SLE.     

PTPN22 Single-Nucleotide Polymorphisms in Iranian Patients with Type 1 Diabetes Mellitus

Background: PTPN22 plays a crucial role in regulating the function of various cells of the immune system, particularly T cells. Polymorphisms of the PTPN22 gene have been associated with many autoimmune diseases, including type 1 diabetes (T1D) which is a T-cell-mediated disease.

Objective: The present study was aimed at genotyping of an Iranian population for five polymorphisms of the PTPN22 gene.

Methods: The study population consisted of 99 T1D patients and 100 healthy controls. We genotyped five single-nucleotide polymorphisms (SNPs) (rs12760457, rs1310182, rs1217414, rs33996649, and rs2476601) of the PTPN22 gene.

Results: Regarding the variant rs2476601, genotypes AG and GG were increased and decreased in T1D patients compared with controls, respectively. Further, alleles G and A of this SNP were found to be decreased and increased in T1D patients, respectively (p value = 0.001). However, T1D and control groups did not differ on genotype distribution or allele frequency for other investigated SNPs.

Conclusions: The PTPN22 rs2476601 minor allele (A) was associated with T1D in Iran, accounting for its pathophysiology in autoimmune diseases.     

Rheumatic Disease Autoantibodies in Autoimmune Liver Diseases

Background: Autoimmune liver diseases (ALDs) are known to be associated with systemic autoimmune rheumatic diseases (SARDs) and their autoantibodies. We aimed to study the prevalence of SARDs and related autoantibodies, as well as their prognostic implications in a group of patients with ALDs.

Methods: This was a cross-sectional study. Sixty patients with ALDs (38.3% with autoimmune hepatitis; 11.7% with primary biliary cirrhosis; 25% with primary sclerosing cholangitis and 25% with overlap syndrome) were studied for the presence of SARDs and their autoantibodies.

Results: There was autoimmune rheumatic disease in 20% of the studied sample. Systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) were the commonest (11.6% and 5%, respectively). Antinuclear antibodies (ANAs) were present in 35% of the patients, followed by anti-Ro (20.0%); anti-nucleosome (18.3%); rheumatoid factor (10%) anti-CCP (8.3%); anti-RNP (8.3%); anti-ds-DNA (6.6%); anti-La (3.3%); anti-Sm (3.3%), anti-ribosomal P (3.3%). Anti-Ro (p = 0.0004), anti-La (p = 0.03), anti-RNP (p = 0.04) and anti-Sm (p = 0.03) were commonly found in patients with SARD, but not anti-DNA, anti-nucleosome and anti-ribosomal P. No differences were found in liver function tests regarding to the presence of autoantibodies.

Conclusions: There was a high prevalence of SARD and their autoantibodies in ALD patients. Anti-Ro, anti-La, anti-RNP and anti-Sm positivity points to an association with systemic autoimmune rheumatic diseases. The presence of autoantibodies was not related to liver function tests.     

Interleukin-4 Gene Intron 3 VNTR Polymorphism in Type 2 Diabetes Patients with Peripheral Neuropathy

Objective: Diabetic peripheral neuropathy (DPN) is one of late complications of diabetes mellitus. The aim of this study was to evaluate the association between variable number tandem repeat (VNTR) polymorphism in intron 3 of interleukin-4 gene and risk of DPN.

Methods: We examined 926 T2DM patients and 420 healthy controls. In the patient group, 44% had DPN. Genomic DNA was isolated from all subjects and genotyped for the IL-4 VNTR polymorphism by polymerase chain reaction (PCR).

Results: No significant difference was observed in the frequency of minor P1 allele between T2DM patients and controls (OR 1.00, 95% CI 0.81–1.23, p = 0.988). The distribution of IL-4 VNTR polymorphism was compared between patients with DPN and those without it. The polymorphism was not significantly associated with DPN in studied subjects. In comparison of 406 T2DM patients with DPN and 520 patients without it, the OR (95% CI) for P1 allele was 0.82 (0.65–1.04), p = 0.10 and for P1P1 genotype 1.00 (0.53–1.89), p = 0.991. When two subgroups of patients with DPN, those with cardiovascular disease (CVD) and without CVD, were compared, subgroup with coexisting CVD had significantly higher frequency of P1 allele than patients without CVD, with odds ratio for the P1 allele 3.27 (95% CI 1.83–5.83), p = 0.0001.

Conclusion: Our results demonstrated that VNTR polymorphism in the IL-4 gene is associated with DPN in type 2 diabetes patients with coexisting CVD.     

The association between rs1893217, rs478582 in PTPN2 and T1D risk with different diagnosed age,and related clinical characteristics in Chinese Han population

Objective: To investigate the association between polymorphisms in PTPN2 (rs1893217 and rs478582) and type 1 diabetes (T1D) risk with different diagnosed age, as well as related clinical characteristics in Chinese Han population.

Methods: A total of 2270 Chinese Han individuals (1023 T1D patients and 1247 healthy controls) were genotyped for rs1893217 and rs478582. And 306 newly diagnosed T1D patients were measured for C-peptide levels based on a standard mixed-meal tolerance test. In addition, 40 healthy controls were analyzed for different T cell subsets by multi-color flow cytometry.

Results: Neither rs1893217 nor rs478582 showed any association with T1D risk under an additive model. Stratified analysis for T1D diagnosed age revealed that rs1893217, but not rs478582, was significantly associated with T1D patients diagnosed age ≤18 (OR =0.80, 95% CI: 0.67–0.97, p?=?0.02). For those diagnosed age >18, neither of them showed any association. We also found that rs1893217 had a higher positive rate of ZnT8A (CC vs. TT carrier, OR = 2.07, 95% CI: 1.07–4.03, p?=?0.026) and IA-2A (CT vs. TT carrier, OR = 1.36, 95% CI: 1.02–1.80, p?=?0.038). Furthermore, for rs478582, compared with TT, healthy individuals carrying CC/CT carriers had significantly lower frequency and Helios expression of naive Treg subsets (p?=?0.049 and 0.048 respectively), but not secreting or activating Treg subsets. In addition, we did not find any association between these two polymorphisms and residual β-cell function in newly diagnosed T1D patients.

Conclusions: Our results suggest that rs1893217 may increase the risk of early-onset T1D and affect humoral immunity, while rs478582 may affect Treg subsets.     

Association between HLA-DQB1 polymorphisms and pemphigus vulgaris: A meta-analysis

Objective: This study was performed to systematically summarize the results on the association of HLA-DQB1 polymorphisms with pemphigus vulgaris (PV) and other related factors.

Methods: A comprehensive literature search of PubMed, The Cochrane Library, Embase, and Google Scholar database was conducted to identify relevant articles in English, with the last report up to November 1, 2016. Heterogeneity test was performed, and publication bias was evaluated. Stata software 12.0 was used to perform the meta-analysis. Odds ratios (ORs) and 95% confidence intervals (CI) were used to describe the correlation by random-effects model.

Results: 18 studies were obtained after searching databases: 10 studies were about Caucasian, and 8 articles were about non-Caucasian. Meta-analysis revealed that the allele and phenotype frequencies of DQB1*05 were markedly higher in PV patients than in controls [P < 0.001, OR: 2.640, 95%CI: 1.570–4.441; P = 0.030, OR 3.688, 95%CI: 1.138–11.946]. In addition, DQB1*03 was significantly increased at the allele level [P < 0.001, OR: 2.080, 95%CI: 1.507–2.869], and DQB1*02 was significantly decreased in PV at the allele and phenotype levels [P = 0.002, OR: 0.450, 95%CI: 0.289–0.702; P = 0.001, OR: 0.293, 95%CI: 0.146–0.587]. When based on each subtype of HLA-DQB1, DQB1*05:03 and DQB1*03:02 may play susceptibility roles in PV, and DQB1*03:03, DQB1*05:01 and DQB1*06:01 are negatively associated with PV.

Conclusion: In summary, our study suggests that alleles from the groups DQB1*05 and DQB1*03, concretely DQB1*05:03 and DQB1*03:02, respectively, may be the susceptibility factors for PV at allele and phenotype levels, whereas DQB1*05:01, DQB1*02, DQB1*06:01, and DQB1*03:03 are negatively associated with PV.     

The Potential Role of PTPN-22 C1858T Gene Polymorphism in the Pathogenesis of Type 1 Diabetes in Saudi Population

Background: Recent investigations have reported an association between protein tyrosine phosphatase non-receptor type-22 (PTPN-22) gene polymorphism and susceptibility to the development of type 1 diabetes (T1D) in some populations and not in others. In this study, we aimed to investigate the association of PTPN-22 C1858T polymorphism with T1D in Saudi children.

Methods: A cohort of 372 type 1 diabetic children and 372 diabetes-free subjects was enrolled in the current investigation. The PTPN-22 C1858T polymorphism was identified using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

Results: Our data showed that the frequency of CT and TT genotypes of PTPN-22 C1858T was higher in T1D children (17.7% and 4.3%, respectively) compared to healthy controls (4.8% and 1.6%, respectively), and both genotypes were statistically associated with T1D patients (OR = 4.4, 95% CI: 2.55–7.58, p < 0.001; and OR = 3.2, 95% CI: 1.23–8.28, p = 0.017, respectively). Moreover, the 1858T allele was significantly associated with T1D patients compared to the C allele (OR = 3.2, 95% CI: 1.59–6.88, p < 0.001). In addition, the T allele was significantly associated with elevated levels of HbA1c, anti-GAD, and anti-insulin antibodies (p < 0.001) and a lower concentration of C-peptide (p < 0.001) in T1D children.

Conclusion: The data presented here suggests that the T allele of PTPN-22 C1858T polymorphism might be a risk factor for T1D development in Saudi children.     

Vitamin D status,aeroallergen sensitization,and allergic rhinitis: A systematic review and meta-analysis

Purpose: The role of vitamin D status in the etiology of allergic diseases is uncertain. The aim of this study was to investigate the association of vitamin D status with risk of two main outcomes: aeroallergen sensitization and allergic rhinitis (AR).

Methods: We performed a systematic review of Medline, Scopus, Science Citation Index, and Google Scholar databases. Studies were included if they reported on prevalent or incident cases of aeroallergen sensitization or AR according to vitamin D status. Quality assessment, data extraction and meta-analysis were performed.

Results: A total of 21 observational studies were included. Children with serum 25(OH)D ≥75 nmol/L had significantly reduced odds of aeroallergen sensitization, but neither vitamin D intake in pregnancy nor vitamin D supplementation in infancy were associated with risk of AR. Individuals with serum 25(OH)D ≥75 nmol/L had lower prevalence of AR compared to those with serum 25(OH)D <50 nmol/L (OR; 0.71, 95%CI; (0.56-0.89), p = 0.04). This association was mainly observed in adult men; prevalence of AR was lower in men with serum 25(OH)D ≥75 nmol/L compared to men with serum 25(OH)D <50 nmol/L, while this association was not observed in women.

Conclusions: The current literature suggests significant age- and sex-specific relations of vitamin D status to risk of aeroallergen sensitization and AR.     

IL12 Gene Polymorphism in Association with Hepatocellular Carcinoma in HCV-infected Egyptian Patients

Background: Hepatocellular carcinoma has been recorded the commonest cancer in Egypt. This increasing incidence may be attributed to the high prevalence of hepatitis C virus with its complications, so this study aimed to investigate the association between the potentially functional polymorphisms of IL12A and IL12B genes as a risk factor of development of hepatocellular carcinoma (HCC) on top of hepatitis C virus (HCV) infection in an Egyptian population.

Materials and methods: We genotyped two loci of IL12 which were rs568408 (3’UTR G>A) for IL12A and rs3212227 (3’UTR A>C) for IL12B in 78 patients with HCC on top of chronic HCV infection. In addition, 64 cancer-free chronic HCV patients were studied, besides 92 healthy subjects who were included as control.

Results: Study of rs568408 (G>A) gene polymorphism showed that the A allele is higher while the G allele is lower in HCC cases than cancer-free chronic HCV patients (p = 0.006*). The A-containing genotypes AG and (AG+AA) were higher while the GG was lower (p = 0.009* and p = 0.005*), respectively. The study of the rs3212227 (A>C) polymorphism showed neither statistically significant differences between the C and A allele (p = 0.2) nor between CC, AC, or AC+CC in HCC cases and cancer-free chronic HCV patients (p = 0.7, p = 0.2, and p = 0.29), respectively.

Conclusion: Our findings showed that IL12A rs568408 (G>A) polymorphism may contribute to the risk of HCC on top of chronic HCV infection, whereas that of IL12B rs3212227 (A>C) do not.     

Mannose-Binding Lectin Deficiency in Brazilian Patients with Spondyloarthritis

Background: Infections are usually involved in the pathogenesis of spondyloarthritis (SpA). Mannose-binding lectin (MBL) is a component of the innate immune system with an important role in microbial defense.

Objective: To study the prevalence of MBL deficiency in SpA patients as well as its influence in the clinical profile of these diseases.

Methods: We studied 89 SpA patients and 89 healthy individuals, paired for age and gender. MBL serum levels were measured by ELISA test. Individuals with levels ≤100 ng/mL were considered deficient. SpA patients had determination of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS)-CRP, Bath Ankylosing Spondylitis Functional Index (BASFI), C reactive protein (CRP), erythrocyte sedimentation rate (ESR), and review of their clinical profile.

Results: SpA patients had MBL levels ranging from 100 to 4100 ng/mL (median = 375 ng/mL); controls levels ranged from 100 to 4703 ng/mL (median = 1204 ng/mL; p < 0.0001). The prevalence of MBL deficiency was 27/89 (30.3%) in SpA patients and 12/89 (13.5%) in controls, with p = 0.01; OR = 2.5 (95% IC = 1.2–5.3). No association/correlation was found between MBL levels with BASDAI, BASFI, age at disease onset, ASDAS-CRP, ESR, CRP, presence of uveitis, HLAB27, peripheral arthritis, or SpA subtype (all p = NS).

Conclusion: MBL levels may be linked with the occurrence of SpA but do not influence its phenotype.     

Matrix Metalloproteinase-9 rs17576 Gene Polymorphism and Behçet’s Disease: Is There an Association?

Background: Clinical studies have reported a significant association between matrix metalloproteinases (MMP), particularly (MMP-9), and inflammatory diseases including Behçet’s disease (BD).

Purpose: To study the relationship between MMP-9 rs17576 gene polymorphism and the development of BD, and its relation to disease activity among Egyptian patients.

Methods: A total of 100 BD patients and 100 healthy control volunteers were genotyped for MMP-9 rs17576 polymorphism with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), followed by the confirmation of our results in random subgroups using direct DNA sequencing technique.

Results: The frequency of the GG genotype and G allele was significantly higher in BD patients as compared to the normal controls (p = 0.011, OR 8.61; p = 0.03, OR 1.65, respectively). There was no significant association between the MMP-9 rs17576 polymorphism and the clinical outcomes of BD.

Conclusion: our study suggests a significant association of the MMP-9 rs17576 A/G polymorphism with increased risk of BD development in Egyptian patients.     

Cytokine Profile in Gout: Inflammation Driven by IL-6 and IL-18?

Introduction: Gout is considered to be an autoinflammatory disease and the presence of monosodium urate (MSU) crystals stimulates activation of NPRL3 inflammasome and subsequently caspase-1, generating production of active IL-1β and IL-18. However, the association between serum cytokines levels and clinical manifestations of the disease is not yet well understood. We evaluated the serum profile of proinflammatory cytokines (IL-1β, IL-6, IL-8, IL-17A, IL-18, IL-22, and IL-23) and described their relationship with clinical and laboratory data.

Methodology: Thirty-nine male patients with gout (GG) were assessed for clinical and laboratory variables and cytokine levels were measured by ELISA. For the purposes of comparison, 34 males with no previous history of arthritis were also included in the study (CG).

Results: Seventeen participants (43%) exhibited active arthritis on evaluation. Levels of IL-18 were significantly higher in patients in relation to the CG (p = 0.0013). No statistically significant differences were found between the GG and CG for the other measured cytokines. There was a moderate correlation between IL-18 and ESR (R = 0.43, p = 0.0073), CRP (R = 0.47, p = 0.0025), and serum levels of IL-6 (R = 0.36, p = 0.023). An association was observed between serum levels of IL-6 and the presence of tophi (p = 0.005) and deformities (p = 0.0008), as well as a correlation between this cytokine and ESR (R = 0.41, p = 0.011) and CRP (R = 0.48, p = 0.02).

Conclusions: IL-18 is associated with inflammatory activity in gout, as well as with IL-6 levels, while IL-6 is associated with clinical and laboratory activity, the presence of tophi and articular deformities, and may be a prognostic marker of this pathology.     

Contribution of Toll-Like Receptor 9 Gene Single-Nucleotide Polymorphism to Systemic Lupus Erythematosus in Egyptian Patients

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease, with multiple genetic and environmental factors involved in its etiology. The toll-like receptor 9 (TLR9) gene has been reported to have important roles in the development and progression of SLE. In this case-control study, the effect of TLR9 polymorphism on susceptibility to SLE was investigated in Egyptian patients.

Methods: We studied the distribution of the TLR9 rs352139 (G + 1174A) single nucleotide polymorphism (SNP) by allele-specific polymerase chain reaction (PCR) in 104 Egyptian patients with SLE and 108 age-, sex-, and ethnically matched controls.

Results: There was no statistically significant difference in the distribution of the AA genotype and alleles between SLE patients and the control group in our study; however, the GA heterozygous patients were three times more likely to develop SLE (P < 0.001). A significant association was detected between TLR9 genotypes and some of the disease manifestations as myositis (p = 0.032), psychosis (p = 0.014), photosensitivity (p = 0.002), and pleurisy (p = <0.001). Moreover, we observed a significant association between the TLR9 AA and GA genotypes and the presence of antinuclear antibodies (ANA) (p = 0.038).

Conclusion: The G + 1174A SNP in the toll receptor 9 gene may contribute to the genetic susceptibility of SLE in Egyptian patients. Also, an influence for this polymorphism on disease manifestations has been elucidated.     

Distribution of xenobiotic metabolising enzyme genotypes in different Tunisian populations

Background: The N-acetyltransferase 2 (NAT2) and glutathione transferase enzymes play a crucial role in the metabolism of xenobiotics. Genetic polymorphisms affecting these enzymes can modify their activities with an effect on individual susceptibility for different pathologies. These metabolic phenotypes occur with varying prevalence in different populations.

Aim: This study sought to analyse the prevalence of important allelic variants of NAT2, GSTM1 and GSTT1 in different Tunisian populations and compare them to other previously reported data.

Subjects and methods: A total of 253 unrelated subjects from different Tunisian populations participated in this study. Subjects were examined with respect to the frequency of slow NAT2, GSTM1*0 and GSTT1*0 genotypes.

Results: The frequency of ‘slow’ NAT2, GSTM1*0 and GSTT1*0 genotypes in the Tunisian population were, respectively, estimated at 23.3%, 53.75% and 29.24%. The frequency of slow NAT2 and GSTM1*0 genotypes were significantly different between the North, Centre and South of Tunisia. However, this study doesn’t report any significant differences in the genotype distribution between Cosmopolitan, Arab and Berber populations.

Conclusions: In conclusion, these data indicate that the Tunisian population is highly heterogenic and, therefore, a strict definition of the populations involved in studies investigating the clinical effect of polymorphisms is required.     

The role of TNF alpha polymorphism and expression in susceptibility to nasal polyposis

Objective: In this study, we first performed a meta-analysis to assess the role of single-nucleotide polymorphism (SNP) within tumor necrosis factor alpha (TNF alpha) gene and TNF alpha expression in the risk of nasal polyposis.

Methods: STATA 12.0 software was utilized to conduct the Mantel–Haenszel statistics, Cohen statistics, Begg’s test, Egger’s tests and sensitivity analysis.

Results: We systemically carried out the database retrieval and initially identified 486 articles. After screening, 15 articles were included in our meta-analysis. For TNF alpha rs1800629 G/A SNP, compared with control group, an increased risk of nasal polyposis of case group was observed in the models of A vs. G [p (P value of association) = 0.009, OR (odds ratio) = 1.35], GA vs. GG (p = 0.001, OR = 1.69), GA+AA vs. GG (p = 0.010, OR = 1.47). The similar results were observed in Caucasian subgroup (p < 0.05, OR > 1). For TNF alpha rs361525 G/A SNP, no significant difference between control and case group was detected (all p > 0.05). In addition, a significant difference exists between case and control groups in the meta-analyses of TNF alpha expression in nasal mucosal cells, secreted TNF alpha (p < 0.05, OR > 1), but not serum TNF alpha (p = 0.090).

Conclusion: The present meta-analysis revealed that TNF alpha rs1800629, increased TNF alpha expression and secretion of nasal mucosal cells were associated with an increased risk of nasal polyposis.