Association analysis of exonic variants of the GABA(B)-receptor gene and alpha electroencephalogram voltage in normal subjects and alcohol-dependent patients

Based on pharmacologic evidence, it has been suggested that GABA_B receptors may play a crucial role in the generation of alpha-electroencephalogram (EEG) oscillations. We tested whether three exonic variants of the gene encoding the human GABA_B receptor (GABA_BR1) modify scalp-recorded alpha-EEG voltage. One hundred twenty-eight patients suffering from alcoholism and 114 normal subjects were investigated. Alcohol-dependent patients were included because evidence exists that the frequently observed alpha low voltage in these subjects is at least partly a trait variable. Logistic regression analyses revealed no associations between alpha-EEG voltage and polymorphic variations in exon 1a1 or exon 11. A significant interaction was observed for an exon 7 substitution polymorphism and diagnosis (P = 0.009). Post hoc analyses showed an association between EEG phenotype and exon 7 genotype in normal subjects only. It is concluded that this particular association may only be observable under physiologic conditions and that alpha low voltage in alcohol-dependent subjects is under the control of either different genes or that it is related to the disease process.     

Semaphorin-3A,semaphorin-7A gene single nucleotide polymorphisms,and systemic lupus erythematosus susceptibility

Abstract

Background: Semaphorin-3A (Sema3A) and Semaphorin-7A (Sema7A) play crucial roles in immune system by inhibiting T cell proliferation and leading to the secretion of pro-inflammatory cytokines. Increasing evidence suggest that Sema3A and Sema7A may link to the development and pathogenesis of systemic lupus erythematosus (SLE).

Objective: This study aims to evaluate the association of Sema3A, Sema7A gene single-nucleotide polymorphisms (SNPs) with susceptibility to SLE.

Methods: There were 495 SLE patients and 493 healthy controls in the study. Sema3A gene and Sema7A gene were genotyped by improved multiple ligase detection reaction (iMLDR), their plasma expression levels were detected by enzyme-linked immunosorbent assay (ELISA).

Results: No differences in genotype and allele frequencies of these SNPs were observed between SLE patients and healthy controls. However, analysing Sema3A and Sema7A SNPs with clinical manifestations of SLE indicated that, in Sema3A, the A allele frequencies of rs7804122 polymorphism was higher in patients with oral ulcers. In Sema7A, there were differences in allele frequencies of the rs2075589 and rs28362930 polymorphisms between SLE patients with haematological disorder and those without. The GG genotype and G allele frequencies of rs28362930 and the CC genotype, and C allele frequencies of rs741761 were both related to discoid rash in SLE patients. The allele frequency of G (rs28362930) was higher in SLE patients with renal disorder. There were differences in the genotype frequencies and allele frequencies of rs741761 between SLE patients with and without arthritis. No differences in plasma Sema3A and Sema7A levels were detected in SLE patients of different genotypes.

Conclusions: Sema3A and Sema7A gene polymorphisms are not related to SLE genetic susceptibility, but may link to several clinical features of SLE.     

Interleukin-4 and Interleukin-4 Receptor Alpha Gene Polymorphisms in Recurrent Aphthous Stomatitis

ABSTRACT

Background: Recurrent aphthous stomatitis (RAS) is a common oral condition with a major impact on the quality of life. The condition is thought to be due to the overexpression of T helper-1(Th1)-related cytokines. Since interleukin-4 (IL-4) and its receptor (IL-4Rα) are antagonistic to Th-1 pathways, polymorphisms in their genes may also be involved in the pathogenesis of aphthous stomatitis.

Methods: Sixty-four patients diagnosed with minor RAS and 141 (age- and sex-matched) healthy controls were assessed for 3 single-nucleotide polymorphisms (SNPs) within the promoter region of the IL-4 gene (?1098G/T, ?590C/T, and ?33C/T), and 1 SNP in IL-4Rα gene (+1902 A/G).

Results: No significant differences were detected between the patient and the control group regarding IL-4 allele frequencies. However, the patient group demonstrated a higher frequency of IL-4 ?590 CC genotype and a lower rate of IL-4 ?590 TC genotype.

The TCT, GTT, GCT, and GTC haplotypes of the IL-4 gene (?1098, ?590, ?33) were significantly more frequent in the patients and the GCC, and TTT haplotypes were more common in healthy controls. No significant differences were found in IL-4Rα gene polymorphism between the 2 groups.

Conclusions: Certain polymorphisms of IL4 gene could predispose individuals to RAS.     

Association analysis of exonic variants of the gene encoding the GABAB receptor and idiopathic generalized epilepsy

The gene encoding the GABA_B receptor (GABA_BR1) maps close to the HLA-F locus on chromosome 6p21.3 in the same region to which a major susceptibility locus for common subtypes of idiopathic generalized epilepsy (IGE), designated as EJM1, has been localized. Moreover, animal models suggest that the GABA_B receptor plays a critical role in the epileptogenesis of absence seizures. Accordingly, the present association study tested the candidate gene hypothesis that genetic variants of the human GABA_BR1 gene confer susceptibility to common subtypes of IGE. Three DNA sequence variants in exons 1a1, 7, and 11 of the GABA_BR1 gene were assessed by PCR-based restriction fragment length polymorphisms in 248 unrelated probands of German descent, comprising 72 patients with juvenile myoclonic epilepsy (JME), 46 patients with idiopathic absence epilepsy (IAE), and 130 control subjects without a history of epileptic seizures and lack of generalized spike-wave discharges in their electroencephalogram. The results revealed no evidence for an allelic association of any of the GABA_BR1 sequence variants with either JME or IAE (P > 0.18). Thus, we failed to demonstrate that any of the three exonic GABA_BR1 variants themselves, or other so-far unidentified mutations, which are in strong linkage disequilibrium with the investigated variants, are involved in the pathogenesis of common IGE subtypes. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 88:305–310, 1999. © 1999 Wiley-Liss, Inc.     

Allelic association analysis of the dopamine D2, D3, 5‐HT2A,and GABAAγ2 receptors and serotonin transporter genes with heroin abuse in Chinese subjects

Five candidate genes, the receptors DRD2, DRD3, HTR2A and GABA_Aγ2, and the serotonin transporter (5‐HTT) were analyzed for association with heroin abuse. We examined three polymorphisms (promoter ? 141ΔC, Ser311Cys, and TaqI) in the DRD2 gene, one polymorphism (Ser9Gly) in the DRD3 gene, two polymorphisms (promoter ? 1438G/A and T102C) in the HTR2A gene, two polymorphisms (VNTR and Del/Ins) in 5‐HTT gene, and one polymorphism (G3145A) in GABA_Aγ2 gene in 121 Chinese heroin addicts and 194 controls. None of the polymorphisms differed significantly for allele, genotype, or haplotype frequencies, except for the DRD2 promoter polymorphism ? 141ΔC (genotype‐wise and allele‐wise, P = 0.05, uncorrected). An additional 344 subjects with heroin abuse and 104 controls were investigated for the ? 141ΔC polymorphism. In the second sample, there were no significant difference of genotype or allele frequencies between subjects with heroin abuse and normal controls. When we divided the sample by route of administration into nasal inhalers and IM or IV injectors, however, it produced a significant difference between inhalers of heroin and controls (genotype‐wise, P = 0.006, allele‐wise, P = 0.016) but not for injectors of heroin (genotype‐wise, P = 0.81, allele‐wise, P = 0.69). We also found that LD between all polymorphisms we examined in the gene was weak, possibly explaining why we see association of this polymorphism with heroin abuse but not with other markers in the gene. Overall our results indicates that the HTR2A, 5‐HTT, DRD3 and GABA_Aγ2 genes are not likely to be a major genetic risk factor for heroin abuse in this population, with the exception of possible association between nasal inhalation and DRD2 promoter ? 141ΔC polymorphism. © 2002 Wiley‐Liss, Inc.     

Association of GABRA2 with Drug Dependence in the Collaborative Study of the Genetics of Alcoholism Sample

Results from twin studies suggest that overlapping genetic factors influence alcohol dependence and illicit drug dependence. Using data from the Collaborative Study on the Genetics of Alcoholism (COGA), we examined the association between 69 SNPs in the GABA_A receptor gene cluster on chromosome 4 and marijuana and illicit drug dependence, individually, and as co-occurring phenotypes with alcohol dependence. Results suggested association between marijuana dependence and illicit drug dependence with SNPs in the GABRA2 gene. Interestingly, the evidence for association previously observed with alcohol dependence came only from individuals with comorbid illicit drug dependence. There was no association with other genes in the GABA_A cluster on chromosome 4 with illicit drug dependence.     

Association analysis of an (AC)n repeat polymorphism in the GABAB receptor gene and schizophrenia

The human γ‐aminobutyric acid type B (GABA_B) receptor gene is a candidate gene for schizophrenia due to its chromosomal location and neurobiologic roles. In the present study, association analyses of genetic polymorphisms of the GABA_B receptor gene with schizophrenia were carried out in 102 unrelated schizophrenic patients and 100 healthy controls, using a polymerase chain reaction‐based, single‐strand conformational polymorphism analysis. Although the Ala20Val and Gly489Ser mutations were not found in our samples, we found a novel polymorphism of (AC)n dinucleotide repeats located approximately 1.6 kb upstream from the translational start site. No significant difference in allele frequencies was found between controls and patients with schizophrenia (P = 0.0587) using the Monte Carlo method. Significant differences were found between controls and patients with continuous‐course schizophrenia (P = 0.0019), and between controls and patients with a positive family history of psychoses (P = 0.0015). These differences, however, were not significant after Bonferroni correction. These data did not support our hypothesis that polymorphisms of the GABA_B receptor gene may confer vulnerability for schizophrenia. © 2002 Wiley‐Liss, Inc.     

Lactase genetic polymorphisms and coeliac disease in children: a cohort study

Background: Lactase activity declines during childhood in the majority of human populations leading to adult-type hypolactasia (AtH). C/T-13910 and G/A-22018 single nucleotide polymorphisms (SNPs) have been suggested to be associated with AtH in different human populations. Coeliac disease (CD) is an autoimmune condition characterized by damage to intestinal cells leading to ultimate deterioration.

Aim: This study investigated the association between coeliac disease (CD) and SNPs leading to AtH in children from North India.

Subjects and methods: Intestinal biopsies and saliva samples were obtained from 52 children with CD diagnosis and 102 control subjects. Biopsies were assayed for disaccharidase activities and samples were genotyped for given SNPs.

Results: Prevalence of C/C and G/G genotypes of AtH was almost equal in the CD and control group. The CD group had low lactase activity compared to the control group, irrespective of genotype at C/T -13910 and G/A -22018 SNPs (p?p?Conclusion: There appears to be no significant correlation between C/T -13910 or G/A -22018 SNPs of AtH and CD. Children with C/C or G/G genotype of AtH may not be at greater risk of CD.     

Interleukin-1β Gene (IL1B) Polymorphism and Risk of Developing Diabetic Nephropathy

Objective: Cytokines play an important role in the pathogenesis of type 2 diabetes (T2DM) and its complications. The aim of the study was to evaluate an association of the ?511 (C/T) polymorphism in the IL1B gene with diabetic nephropathy (DN).

Methods: The study population included 860 patients with T2DM (506 with diabetic nephropathy and 354 without nephropathy) as well as 505 healthy individuals. Genomic DNA was genotyped for the IL1B ?511 (C/T) polymorphism using PCR-RFLP technique.

Results: The IL1B ?511 C/T polymorphism was genotyped in 860 T2DM patients with or without DN and 505 healthy individuals. The average age of patients was 65.3 years in DN+ and 62.2 years in DN- subgroups. The genotype distribution did not differ significantly between patients and controls. Only a tendency to a slight increase of T allele frequency was observed in patient group. Genotype and allele frequencies of ?511 C/T polymorphism were compared in patients with DN and those without it. The minor allele (T) and homozygote TT frequencies were significantly different between subgroups. The T allele was more frequent in DN+ patients, with odds ratio 1.45 (95% CI 1.2–1.8), p = 0.0003. The TT genotype frequency was also higher in DN+, with OR 1.76 (96% CI 1.1–2.7), p = 0.01.

Conclusion: In a studied population the ?511 C/T polymorphism in the IL1B gene is associated with diabetic nephropathy in dialyzed T2DM patients. Further studies are required to confirm the clinical significance of this finding.     

Evaluation of 64 candidate single nucleotide polymorphisms as risk factors for neural tube defects in a large Irish study population

Individual studies of the genetics of neural tube defects (NTDs) contain results on a small number of genes in each report. To identify genetic risk factors for NTDs, we evaluated potentially functional single nucleotide polymorphisms (SNPs) that are biologically plausible risk factors for NTDs but that have never been investigated for an association with NTDs, examined SNPs that previously showed no association with NTDs in published studies, and tried to confirm previously reported associations in folate‐related and non‐folate‐related genes. We investigated 64 SNPs in 34 genes for association with spina bifida in up to 558 case families (520 cases, 507 mothers, 457 fathers) and 994 controls in Ireland. Case‐control and mother‐control comparisons of genotype frequencies, tests of transmission disequilibrium, and log‐linear regression models were used to calculate effect estimates. Spina bifida was associated with over‐transmission of the LEPR (leptin receptor) rs1805134 minor C allele [genotype relative risk (GRR): 1.5; 95% confidence interval (CI): 1.0–2.1; P = 0.0264] and the COMT (catechol‐O‐methyltransferase) rs737865 major T allele (GRR: 1.4; 95% CI: 1.1–2.0; P = 0.0206). After correcting for multiple comparisons, these individual test P‐values exceeded 0.05. Consistent with previous reports, spina bifida was associated with MTHFR 677C>T, T (Brachyury) rs3127334, LEPR K109R, and PDGFRA promoter haplotype combinations. The associations between LEPR SNPs and spina bifida suggest a possible mechanism for the finding that obesity is a NTD risk factor. The association between a variant in COMT and spina bifida implicates methylation and epigenetics in NTDs. © 2010 Wiley‐Liss, Inc.     

Interleukin 28A.rs12980602 and interleukin 28B.rs8103142 genotypes could be protective against HCV infection among Egyptians

Previous studies showed that interleukin (IL)-28B gene polymorphisms were associated with hepatitis C Virus (HCV) infection and treatment outcomes. We tested whether single-nucleotide polymorphisms (SNPs) in IL-28A and IL-28B are associated with HCV infection among Egyptians with HCV genotype 4 infections. We enrolled 144 chronic HCV patients, 72 spontaneously resolved HCV subjects, and 69 healthy controls. Four SNPs in IL-28A and IL-28B genes (IL-28A.rs12980602, IL-28B.rs12979860, IL-28B.rs8099917, and IL-28B.rs8103142) were genotyped. The most frequent IL-28B haplotype “TCT” was significantly more frequent in HCV-infected subjects than in HCV negative subjects (62.2% vs. 48.6%, respectively; p = 0.005). The frequency of IL-28A.rs12980602 “T” allele was significantly higher than the “C” allele in healthy controls compared to HCV-infected subjects (p < 0.001) with the “TT” genotype significantly higher in healthy controls compared to HCV-infected subjects (p < 0.001) with no association with viral load (p = 0.11) among chronically infected subjects. The results, also, confirmed the previous role of IL-28B SNPs in predicting HCV infection outcome. Importantly, IL-28B.rs8099917 “TT” genotype was significantly associated with low viral load in HCV-infected subjects, while the remaining three SNPs did not. The three IL-28B SNPs were in linkage disequilibrium (D′ > 0.68; r² > 0.43) for all comparisons in HCV patients, while there was no linkage disequilibrium of IL-28A polymorphisms and the three IL-28B SNPs. In conclusion, IL-28A.rs12980602 and IL-28B.rs8103142 TT genotype could be protective against HCV infection. Also, IL-28B.rs12979860, IL-28B.rs8099917, and IL-28B.rs8103142 SNPs predicted the outcome of HCV infection among genotype-4-infected Egyptians. Moreover, IL-28B.rs8099917 SNP affected the viral load in chronic HCV patients.

     

Levels of Interleukin‐(IL)‐12p40 are Markedly Increased in Brucellosis Among Patients with Specific IL‐12B Genotypes

Brucellosis remains a major zoonosis worldwide. Brucella antigens induce the production of T‐helper 1 (Th1) cytokines such as interleukin‐12 (IL‐12) in humans. We aimed to investigate the association of two single nucleotide polymorphisms (SNPs) in the gene encoding the IL‐12p40 cytokine (IL‐12B) with brucellosis and to examine the functionality of these SNPs through measuring serum levels of IL‐12p40. We genotyped IL‐12B gene rs3212227, A>C; rs6887695 G>C polymorphisms in a case‐control study on a total of 281 subjects including 153 patients with active brucellosis and 128 healthy controls, using RFLP and serum IL‐12p40 levels, were assessed by ELISA. The rs3212227 minor allele (C) and homozygote genotype (CC) were more frequent in controls compared with patients with brucellosis (P = 0.006, OR = 0.608, 95%CI = 0.429–0.861 for the C allele; P = 0.024, OR = 0.443, 95% CI: 0.218–0.900 for the CC genotype). Comparison of IL‐12B genotypes and serum levels of the IL‐12p40 revealed that rs3212227 AA genotype, with higher frequency in patients than in controls, was associated with increased levels of the cytokine (P = 0.0001). Furthermore, the distribution of haplotype and genotype combinations in our study suggested that rs3212227C/rs6887695C haplotype or CC/GC or CC/CC genotype combinations may protect controls against Brucella infection by contributing to a functional downregulation of the serum IL‐12p40 production in vivo, as shown by ELISA (P < 0.05). Overall, our study demonstrated that rs3212227 A variant was associated with higher levels of serum IL‐12p40 and could possibly contribute to an inherited predisposition to brucellosis.     

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.     

Polymorphisms of inflammation‐related genes and colorectal cancer risk: a population‐based case–control study in China

The previous studies found that chronic inflammation related to an increased risk of colorectal cancer (CRC). This study aims to explore the associations of polymorphisms in inflammation‐related genes (IL10, IL10RA, IL6R, TNFRSF1A, TNFRSF1B, LTA and IL4) and their interactions with the risk of colorectal cancer among Chinese population. A population‐based case–control study including 299 cases and 296 controls was conducted from January 2001 to December 2009. Multivariate unconditional logistic regression was used to analyse the association of nine SNPs in inflammation‐related genes with the risk of CRC, colon cancer and rectal cancer, respectively. Generalized multifactor dimensionality reduction (GMDR) was implemented to explore the gene–gene interactions among all SNPs on CRC. A decreased risk of colorectal cancer in subjects with rs1800872 AC genotype of IL10 (OR = 0.643, 95%CI = 0.453, 0.912) or AC/CC genotype (OR = 0.636, 95%CI = 0.457, 0.885) was observed, compared with those with AA genotype. Meanwhile, similar associations were observed between rs1800872 and rectal cancer. Additionally, in rs1061624 of TNFRSF1B gene, AG genotype (OR=0.566; 95% CI= 0.362, 0.885) and AG/GG genotype (OR=0.638; 95% CI=0.420, 0.971) were significantly associated with a decreased risk of rectal cancer, respectively. Our findings indicated that mutants in IL10 and TNFRSF1B genes may change the CRC risk. However, there is no interaction between inflammation‐related genes on CRC risk.     

Genetic association of interleukin-1 haplotypes with gastritis and precancerous lesions in North Indians

Background We evaluated the association of functional variants of IL-1 genes with the development of gastritis and precancerous lesions, which are known to be influenced by inflammatory response against Helicobacter pylori. Methods After upper gastrointestinal (GI) endoscopy, 120 patients with gastritis were tested for H. pylori infection using rapid urease test, modified Giemsa staining and IgG anti-CagA ELISA. All patients and 243 healthy controls were genotyped for IL-1B (-511 C/T) and IL-IRN (VNTR) genes using PCR-RFLP/PCR. Results IL-1B (−511 C/T) genotype/allele were not associated with gastritis. IL-1RN 1/2 genotype carriers had susceptibility to gastritis (p = 0.025, OR = 1.7). Individuals with the IL-1RN 1/1 genotype (p = 0.05, OR = 0.65) and IL-1B −511*T-IL-1RN *1 haplotype were at low risk for gastritis (p = 0.043, OR = 0.72). High secretor haplotype combinations (C1-/T2+, C1-T1+ and T1+/T2+) did not influence neutrophilic infiltration, glandular atrophy or intestinal metaplasia. Conclusions We identified that individuals with the IL-1RN 1/2 genotype had increased risk for gastritis. IL-1B −511*T-IL-1RN *1 (T1) haplotype carriers were at decreased risk for gastritis and no significant association was observed for precancerous lesions in North Indians.     

Association Analysis of Chromosome 15 GABAA Receptor Subunit Genes in Autistic Disorder

Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the brain, acting via the GABA_A receptors. The GABA_A receptors are comprised of several different homologous subunits, forming a group of receptors that are both structurally and functionally diverse. Three of the GABA_A receptor subunit genes (GABRB3, GABRA5 and GABRG3) form a cluster on chromosome 15q11-q13, in a region that has been genetically associated with autistic disorder (AutD). Based on these data, we examined 16 single nucleotide polymorphisms (SNPs) located within GABRB3, GABRA5 and GABRG3 for linkage disequilibrium (LD) in 226 AutD families (AutD patients and parents). Genotyping was performed using either OLA (oligonucleotide ligation assay), or SSCP (single strand conformation polymorphism) followed by DNA sequencing. We tested for LD using the Pedigree Disequilibrium Test (PDT). PDT results gave significant evidence that AutD is associated with two SNPs located within the GABRG3 gene (exon5_539T/C, p = 0.02 and intron5_687T/C, p = 0.03), suggesting that the GABRG3 gene or a gene nearby contributes to genetic risk in AutD.     

Association between rs6887695 and 3′-untranslated region polymorphisms within the interleukin-12B gene and susceptibility to autoimmune diseases in Asian and European population: A meta-analysis

Background: The associations between rs6887695 and 3′-untranslated region (3′-UTR) single-nucleotide polymorphisms (SNPs) within interleukin-12B (IL-12B) and autoimmune diseases (ADs) remain controversial and inconclusive. The aim of this study was to evaluate the association between IL-12B (3′-UTR A/C and rs6887695 C/G SNPs) and ADs by meta-analysis. Methods: PubMed and EMBASE were exhaustively searched for studies on the association between IL-12B SNPs and ADs. Publication bias was examined by a funnel plot and Egger’s test. The robustness of the pooled results was assessed by sensitivity analysis. A fixed- or a random-effects model was applied to calculate the pooled odds ratios (ORs). Results: A total of 34 studies were included in this meta-analysis. The pooled results demonstrated that IL-12B rs6887695 SNPs were significantly associated with the risk of ADs. However, there was no significant association between IL-12B 3′-UTR SNPs and ADs. When the studies were stratified by ethnicity, significant association between IL-12B 3′-UTR SNPs and ADs was observed in both Asian and European population. In addition, allele A within 3′-UTR of IL-12B gene was found to be a protective factor for T1DM, but a risk factor for psoriasis. Conclusion: The IL-12B 3′-UTR and rs6887695 SNPs are associated with susceptibility to ADs.     

Meta-Analysis of the Relationship between TNF-α (−308G/A) and IL-10 (−819C/T) Gene Polymorphisms and Susceptibility to Dengue

Objective: This study determined whether tumor necrosis factor alpha (TNF-α) and Interleukin-10 (IL-10) polymorphisms are associated with susceptibility to dengue.

Methods: a systematic review with meta-analysis was conducted of the associations between the TNF-α (?308G/A) and IL-10 (?819C/T) polymorphisms and dengue.

Results: A total of eight case-controls studies involving 384 individuals with symptomatic dengue, 571 individuals with dengue hemorrhagic fever, and 995 healthy controls were considered in the meta-analysis. There was no significant association between TNF-α (?308G/A) and IL-10 (?819C/T) polymorphism and dengue in overall population. However, stratifying meta-analysis by groups, the meta-analysis revealed association between the TNF-α ?308 G/G (OR: 1.62, CI: 1.02–2.57, p = 0.04) genotype and allele G (OR: 1.62, CI: 1.04–2.55, p = 0.03) that confers susceptibility to symptomatic dengue, while the TNF-α ?308 G/A genotype (OR: 0.69, CI = 0.39–0.99, p = 0.04) and allele A (OR: 0.64, CI: 0.41–1.00, p = 0.05) confers protection to symptomatic dengue. No difference was observed for the TNF-α (?308) and IL-10 (?819C/T) polymorphisms in the comparisons of hemorrhagic dengue versus control and hemorrhagic dengue versus symptomatic dengue.

Conclusion: This meta-analysis showed that TNF-α (?308) polymorphism is associated with dengue symptomatic susceptibility.     

Exon 33 T/T genotype of the thyroglobulin gene is a susceptibility gene for Graves’ disease in Taiwanese and exon 12 C/C genotype protects against it

This study investigates whether Tg gene polymorphisms can be associated with Graves’ disease (GD) in a Taiwanese population and identifies potential polygenic susceptive genes for GD. The findings of such a study may have important implications for prognostic prediction and treatment of GD. We performed case control association studies for the 3 discovered Tg single nucleotide polymorphisms (SNPs) (E10, E12, E33) in 215 GD patients and 141 controls. The three SNPs were identified within the Tg gene. These SNPs were analysed by a fluorescent-based restriction fragment length polymorphism method (RFLP) and PCR. The genotype and allele frequencies at E10SNP158, E12SNP and E33SNP in GD patients were compared with those of the controls. In addition, we analysed the interactions between these SNPs and the clinical and laboratory variables. We found a significant difference in the T/T genotype of E33SNP and G/G genotype of E12SNP compared with the control group (p < 0.001). We also found the E33SNP T/T genotype to be positively associated with development of GD, whereas the E12SNP G/G genotype protected it.