128 resultados para Cyp1a1 Polymorphisms


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Background: The CCR5 32-base deletion (CCR5D32), which results into the expression of a non-functioning receptor, has been associated with H CV c learance a nd may influence fibrosis progression i n hepatitis C . We a ssessed t he link between C CR5D32 and c linical outcomes o f HCV. Methods: Genomic D NA was isolated and analyzed b y PCR to i dentify C CR5D32 in 1 303 anti-HCV-positive persons (161 clearers and 1142 chronically infected, 1007 with a liver biopsy). Results: Overall, 200 (15.3%) w ere heterozygote a nd 16 (1.2%) homozygote for CCR5D32. H CV c learance (by univariate) was associated with m ale sex (OR 0.633, 9 5% C I 0.428-0.935, P=0.022), HCV acquisition by blood transfusion (OR 0.360, 95% CI 0.175-0.741, P =0.0056), polymorphisms at IL28B rs12979860 ( OR 0.482, 9 5% C I 0.277-0.839, P =0.0098) a nd rs8099917 ( OR 0.291, 95% CI 0.167-0.508, P=0.000014), but not with CCR5D32. However, CCR5D32 was associated with spontaneous HCV clearance when the 482 females only w ere considered, although the number of homozygotes was small (1/427 chronic vs 3/51 clearers) (OR 24.56, 95% C I 12.5-241.4, P =0.006). T he CCR5D32 deletion was not associated with liver grading and staging scores, fibrosis progression rate, or t herapy response. Conclusions: At v ariance w ith a p revious report (Nattermann et a l, 2011), suggesting that a n on-functional CCR5 m ay hamper H CV clearance, C CR5D32 appeared to b e associated with an increased spontaneous eradication in women (but not men). Given the small number of CCR5D32 homozygote persons, these data need further validation.

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AIMS/HYPOTHESIS: Paraoxonase is a member of a multigene family of three genes. Paraoxonase2 gene polymorphisms have been associated with coronary heart disease in non-diabetic patients and with an increased fasting glycaemia in patients with Type II (non-insulin-dependent) diabetes mellitus. We tested the hypothesis of whether paraoxonase1 and paraoxonase2 polymorphisms were associated with diabetic nephropathy. METHODS: Our case-control study of 299 Swiss patients with Type II diabetes included 147 patients with confirmed diabetic nephropathy. RESULTS: In univariate analyses the two paraoxonase2 polymorphisms were associated with diabetic nephropathy. When subjected to multivariate analyses, both paraoxonase2 polymorphisms remained statistically associated with diabetic nephropathy independent of traditional risk factors (paraoxonase2-148: OR = 2.53, p = 0.003; paraoxonase2-311: OR = 2.67, p = 0.002). In addition, BMI interacted with paraoxonase2 polymorphisms as a risk factor of nephropathy. CONCLUSIONS/INTERPRETATION: The paraoxonase2 gene polymorphisms were significantly associated with diabetic nephropathy independent of traditional risk factors in Type II diabetic patients. The susceptibility to diabetic nephropathy was intensified by the degree of obesity. Pathophysiological pathways should be investigated and could be involved in insulin resistance or lipids metabolism or both.

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In Arabidopsis thaliana, gene expression level polymorphisms (ELPs) between natural accessions that exhibit simple, single locus inheritance are promising quantitative trait locus (QTL) candidates to explain phenotypic variability. It is assumed that such ELPs overwhelmingly represent regulatory element polymorphisms. However, comprehensive genome-wide analyses linking expression level, regulatory sequence and gene structure variation are missing, preventing definite verification of this assumption. Here, we analyzed ELPs observed between the Eil-0 and Lc-0 accessions. Compared with non-variable controls, 5' regulatory sequence variation in the corresponding genes is indeed increased. However, approximately 42% of all the ELP genes also carry major transcription unit deletions in one parent as revealed by genome tiling arrays, representing a >4-fold enrichment over controls. Within the subset of ELPs with simple inheritance, this proportion is even higher and deletions are generally more severe. Similar results were obtained from analyses of the Bay-0 and Sha accessions, using alternative technical approaches. Collectively, our results suggest that drastic structural changes are a major cause for ELPs with simple inheritance, corroborating experimentally observed indel preponderance in cloned Arabidopsis QTL.

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Background & Aims: Single nucleotide polymorphisms (SNPs) associated with IL28B influence the outcome of peginterferon-alpha/ribavirin therapy of chronic hepatitis C virus (HCV) infection. We analyzed the kinetics of HCV RNA during therapy as a function of IL28B SNPs.Methods: IL28B SNPs rs8099917, rs12979860, and rs12980275 were genotyped in 242 HCV treatment-naive Caucasian patients (67% genotype 1, 28% genotype 2 or 3) receiving peginterferon-alpha 2a (180 mu g weekly) and ribavirin (1000-1200 mg daily) with serial HCV-RNA quantifications. Associations between IL28B polymorphisms and early viral kinetics were assessed, accounting for relevant covariates.Results: In the multivariate analyses for genotype 1 patients, the T allele of rs12979860 (T(rs12979860)) was an independent risk factor for a less pronounced first phase HCV RNA decline (log(10) 0.89 IU/ml among T carriers vs. 2.06 among others, adjusted p <0.001) and lower rapid (15% vs. 38%, adjusted p = 0.007) and sustained viral response rates (48% vs. 66%, adjusted p <0.001). In univariate analyses, Trs12979860 was also associated with a reduced second phase decline (p = 0.002), but this association was no longer significant after adjustment for the first phase decline (adjusted p = 0.8). In genotype 2/3 patients, Trs12979860 was associated with a reduced first phase decline (adjusted p = 0.04), but not with a second phase decline.Conclusions: Polymorphisms in IL28B are strongly associated with the first phase viral decline during peginterferon-alpha/ribavirin therapy of chronic HCV infection, irrespective of HCV genotype. (C) 2011 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

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Rapport de synthèse :Les individus HIV-positifs constituent une population à risque pour les maladies cardiovasculaires telles que |'infarctus cardiaque ou cérébrale. Celles-ci découlent d'une formation accélérée d'athéroscIérose. Ces pathologies s'expliquent en grande partie par une dyslipidémie observée au sein de cette population et qui sont dues à des facteurs externes tels que : l'immunosuppression avancée, la virémie non-contrôlée, et les effets de la thérapie antirétrovirale. Récemment, des polymorphismes nucléotidiques simples (SNP) associés à la dyslipidémie ont été mis en évidence d'une manière globale par des Genome-Wide Association Studies (GWAS). Le but principal de cette étude est d'éva|uer et de valider |'effet cumulatif des SNP identifiés dans ces GWAS pour la dyslipidémie chez des patients HIV-positifs. De plus, |'identification des facteurs non-génétiques qui contribuent à la dyslipidémie démontrent |'importance des facteurs externes, tels que mentionnés ci- dessus, et en particulier à ceux de la thérapie antirétrovirale.Les participants de l'étude proviennent de trois groupes: 426 personnes sélectionnées pour une étude précédente, 222 personnes sélectionnées de façon arbitraire dans la "Cohorte HIV Suisse" et 103 personnes sélectionnées avec un "New-Onset Diabetes mellitus" identifiées lors d'études précédentes. Ces individus ont contribué à plus de 34'000 mesures de lipides sur une durée moyenne supérieure à 7 ans. Pour l'étude, 33 SNP identifiés dans des GWAS et 9 SNP identifiés dans d'autres études publiées dans la littérature non-couverte par des GWAS ont été repris. Le génotypage a été complété pour 745 (99.2%) des 751 participants. Pour les analyses statistiques, les thérapies antirétrovirales ont été divisées en trois groupes (favorisant peu, moyennement et fortement la dyslipidémie), et trois scores génétiques ont été créés (profil favorable, moyennement favorable, non favorable/favorisant la dyslipidémie). Dans un premier temps, l'effet sur la valeur des lipides d'un ou deux allèles variants a été analysé au moyen d'un modèle de régression pour chaque SNP en ajustant le modèle pour les variables non- génétiques. Dans un deuxième temps, les SNP ayant une valeur p >= à 0.2 ont été repris dans un model Multi-SNP, ce modèle est également ajusté pour les variables non-génétiques. Puisque cette étude se base sur des SNP précédemment identifiés, celle-ci évalue uniquement l'association établie entre chaque SNP et les critères qui ont été établis au préalable, tels que : Cholestérol totale, HDL Cholestérol, non-HDL Cholestérol ou Triglycérides. Les résultats trouvés lors de |'étude confirment les résultats de la littérature. Cette étude montre que les SNP associés à la dyslipidémie doivent être analysés dans le contexte d'une thérapie antirétrovirale en tenant compte de la démographie et en considérant les valeurs du HIV (CD4+, virémie). Ces SNP montrent une tendance à prédire une dyslipidémie prolongée chez l'individu. En effet, un patient avec une thérapie antirétrovirale favorisant la dyslipidémie et un patrimoine génétique non-favorable a un risque qui est 3-f0is plus important d'avoir un Non-HDL- Cholestérol élevé, 5-fois plus important d'avoir un HDL-Cholestérol abaissé, et 4 à 5-fois plus important d'avoir une hypertriglycéridémie qu'un patient qui suit une thérapie antirétrovirale favorisant peu la dyslipidémie qui a un patrimoine génétique favorable. Vu la corrélation entre les SNP et la thérapie antirétrovirale, les cliniciens devraient intégrer les informations génétiques afin de choisir une thérapie antirétrovirale en fonction du patrimoine génétique.

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Aims: The adaptive immune response against hepatitis C virus (HCV) is significantly shaped by the host's composition of HLA alleles. Thus, the HLA phenotype is a critical determinant of viral evolution during adaptive immune pressure. Potential associations of HLA class I alleles with polymorphisms of HCV immune escape variants are largely unknown. Methods: Direct sequence analysis of the genes encoding the HCV proteins E2, NS3 and NS5B in a cohort of 159 patients with chronic HCV genotype 1 infection who were treated with pegylated interferon-alfa 2b and ribavirin in a prospective controlled trial for 48 weeks was exhibited. HLA class I genotyping was performed by strand-specific reverse hybridization with the INNO-LiPA line probe assays for HLA-A and HLA-B and by strand-specific PCR-SSP. We analyzed each amino acid position of HCV proteins using an extension of Fisher's exact test for associations with HLA alleles. In addition, associations of specific HLA alleles with inflammatory activity, liver fibrosis, HCV RNA viral load and virologic treatment outcome were investigated. Results: Separate analyses of HCV subtype 1a and 1b isolates revealed substantially different patterns of HLA-restricted polymorphisms between subtypes. Only one polymorphism within NS5B (V2758x) was significantly associated with HLA B*15 in HCV genotype 1b infected patients (adjusted p=0,048). However, a number of HLA class I-restricted polymorphisms within novel putative HCV CD8+ T cell epitopes (genotype 1a: HLA-A*11 GTRTIASPK1086-1094 [NS3], HLA-B*07 WPAPQGARSL1111-1120 [NS3]; genotype 1b: HLA-A*24 HYAPRPCGI488-496 [E2], HLA-B*44 GENETDVLL530-538 [E2], HLA-B*15 RVFTEAMTRY2757-2766 [NS5B]) were observed with high predicted epitope binding scores assessed by the web-based software SYFPEITHI (>21). Most of the identified putative epitopes were overlapping with already otherwise published epitopes, indicating a high immunogenicity of the accordant HCV protein region. In addition, certain HLA class I alleles were associated with inflammatory activity, stage of liver fibrosis, and sustained virologic response to antiviral therapy. Conclusions: HLA class I restricted HCV sequence polymorphisms are rare. HCV polymorphisms identified within putative HCV CD8+ T cell epitopes in the present study differ in their genomic distribution between genotype 1a and 1b isolates, implying divergent adaptation to the host's immune pressure on the HCV subtype level.

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Résumé : Dans le but d'examiner les facteurs génétiques qui influencent la pharmacocinétique de la clozapine in vivo, 75 patients traités avec ce médicament antipsychotique ont été genotypés pour les polymorphismes CYP et ABCB1, et phénotypés pour l'activité de CYP1A2 et CYP3A. L'activité de CYP1A2 et les taux plasmatiques de clozapine en steady-state corrèlent d'une manière significative (r=0.61; p=1x10), sans influence du génotype de CYP1A2*1F (p=0.38). Les métaboliseurs déficients CYP2C19 (génotype *2/*2 genotype) avaient des concentrations de clozapine 2,3 fois (p=0.036) plus élevées que les métaboliseurs rapides (non*2/*2). Chez les patients comédiqués avec la fluvoxamine, un fort inhibiteur de CYP1A2, les concentrations de clozapine et de norclozapine corrèlent significativement avec l'activité de CYP3A (r=0.44, p=0.075; r=0.63, p=0.007, respectivement). Les porteurs du génotype ABC81 3435TT avaient des concentrations plasmatiques de clozapine 1,6 fois plus élevées que ceux qui ne présentaient pas ce génotype (p=0.046). En conclusion, cette étude montre pour la première fois, in vivo, le rôle significatif de CYP2C19 et celui du transporteur P-gp dans la pharmacocinétique de la clozapine. Le CYP1A2 est la forme principale de CYP impliquée dans le métabolisme de clozapine, tandis que le CYP2C19 joue un rôle modéré et que le CYP3A4 n'y contribue que chez les patients qui présentent une activité de CYP1A2 réduite. De plus, le polymorphisme de ABC81, mais pas ceux de CYP2B6, CYP2C9, CYP2D6, CYP3A5 et CYP3A7, influence la pharmacocinétique de la clozapine. Abstract : To examine the genetic factors influencing clozapine kinetics in vivo, 75 patients treated with clozapine were gcnotyped for CYPs and ABCBI polymorphisms and phenotyped for CYPIA2 and CYP3A activity. CYPIA2 activity and dose-corrected trough stéady-state plasma concentrations of clozapine correlated significantly (r = -0.61; P = 1 x 10 pow(-6), with no influence of the CYPIA2*IF genotype (P = 0.38). CYP2C 19 poor metabolizers (*2/*2 genotype) had 2.3-fold higher (P = 0.036) clozapine concentrations than the extensive metabolizers (non-*2/*2). In patients comedicated with fluvoxamine, a strong CYPlA2 inhibitor, clozapine and norclozapine concentrations correlate with CYP3A activity (r = 0.44, P = 0.075; r = 0.63, P = 0.007, respectively). Carriers of the ABCB1 3435TT genotype had a 1.6-fold higher clozapine plasma concentrations than noncarriers (P = 0.046). In conclusion, this study has shown for the first time a significant in vivo role of CYP2C19 and the P-gp transporter in the pharmacokinetics of clozapine. CYPlA2 is the main CYP isoform involved in clozapine metabolism, with CYP2C19 contributing moderately, and CYP3A4 contributing only in patients with reduced CYPIA2 activity. In addition, ABCBI, but not CYP1B6, CYP1C9, CYP1D6, CYP3A5, nor CYP3A7 polymorphisms, influence clozapine pharmacokinetics.

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BACKGROUND: Toll-like receptors (TLRs) are essential components of the immune response to fungal pathogens. We examined the role of TLR polymorphisms in conferring a risk of invasive aspergillosis among recipients of allogeneic hematopoietic-cell transplants. METHODS: We analyzed 20 single-nucleotide polymorphisms (SNPs) in the toll-like receptor 2 gene (TLR2), the toll-like receptor 3 gene (TLR3), the toll-like receptor 4 gene (TLR4), and the toll-like receptor 9 gene (TLR9) in a cohort of 336 recipients of hematopoietic-cell transplants and their unrelated donors. The risk of invasive aspergillosis was assessed with the use of multivariate Cox regression analysis. The analysis was replicated in a validation study involving 103 case patients and 263 matched controls who received hematopoietic-cell transplants from related and unrelated donors. RESULTS: In the discovery study, two donor TLR4 haplotypes (S3 and S4) increased the risk of invasive aspergillosis (adjusted hazard ratio for S3, 2.20; 95% confidence interval [CI], 1.14 to 4.25; P=0.02; adjusted hazard ratio for S4, 6.16; 95% CI, 1.97 to 19.26; P=0.002). The haplotype S4 was present in carriers of two SNPs in strong linkage disequilibrium (1063 A/G [D299G] and 1363 C/T [T399I]) that influence TLR4 function. In the validation study, donor haplotype S4 also increased the risk of invasive aspergillosis (adjusted odds ratio, 2.49; 95% CI, 1.15 to 5.41; P=0.02); the association was present in unrelated recipients of hematopoietic-cell transplants (odds ratio, 5.00; 95% CI, 1.04 to 24.01; P=0.04) but not in related recipients (odds ratio, 2.29; 95% CI, 0.93 to 5.68; P=0.07). In the discovery study, seropositivity for cytomegalovirus (CMV) in donors or recipients, donor positivity for S4, or both, as compared with negative results for CMV and S4, were associated with an increase in the 3-year probability of invasive aspergillosis (12% vs. 1%, P=0.02) and death that was not related to relapse (35% vs. 22%, P=0.02). CONCLUSIONS: This study suggests an association between the donor TLR4 haplotype S4 and the risk of invasive aspergillosis among recipients of hematopoietic-cell transplants from unrelated donors.

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Glutamate cysteine ligase (GCL) catalyzes the rate-limiting step in the de novo synthesis of glutathione (GSH). The catalytic subunit (GCLC) of GCL contains a GAG trinucleotide-repeat (TNR) polymorphism within the 5'-untranslated region (5'-UTR) that has been associated with various human disorders. Although several studies suggest that this variation influences GSH content, its implication for GCLC expression remains unknown. To better characterize its functional significance, we performed reporter gene assays with constructs containing the complete GCLC 5'-UTR upstream of a luciferase gene. Transfection of these vectors into various human cell lines did not reveal any significant differences between 7, 8, 9, or 10 GAG repeats, under either basal or oxidative stress conditions. To correlate these results with the previously described down-regulation induced by the C-129T GCLC promoter polymorphism, combinations of both variations were tested. Interestingly, the -129T allele down-regulates gene expression when combined with 7 GAG but not with 8, 9, or 10 GAG TNRs. This observation was confirmed in primary fibroblast cells, in which the combination of GAG TNR 7/7 and -129C/T genotypes decreased the GCLC protein level. These results provide evidence that interaction of the two variations can efficiently impair GCLC expression and thus suggest its involvement in the pathogenesis of diseases related to GSH metabolism.

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Aims: Cytochrome P4501A2 (CYP1A2) is involved in the metabolism of severaldrugs (clozapine, olanzapine, theopylline, caffeine, etc) and is induced by smoking.This can result in decreased plasma levels of drugs metabolized by thisisoenzyme, causing a decrease in therapeutic response. After quitting smoking,increased plasma levels can lead to adverse effects of the concerned drugs, such asconfusion and seizures, described under clozapine treatment. The present studyaimed to examine the variation of CYP1A2 activity in a large group of smokersbefore and after smoking cessation. Moreover, we aimed to determine whethergenetic polymorphisms of CYP1A2 gene could influence the inducibility ofCYP1A2. Methods: CYP1A2 activity was determined by the paraxanthine/caffeineratio in 194 smokers and in 118 of them being abstinent during a 4-weekperiod. Participants were genotyped for CYP1A2*1F (rs762551), *1D(rs35694136) and *1C (rs2069514) polymorphisms. Results: Smokers had higherCYP1A2 activity (1.55-fold; p < 0.0001). Individual change of CYP1A2 activityafter smoking cessation ranged from 1.0-fold (no change) to 7.3-fold decreasedactivity. In five participants with low initial CYP1A2 activity, an increase wasobserved after smoking cessation. During smoking, CYP1A2*1F (p = 0.005), CYP1A2*1D (p = 0.014), the number of cigarettes/day (p = 0.012), contraceptives use(p < 0.001) and - 163A/- 2467T/- 3860G haplotype (p = 0.002) influencedCYP1A2 activity, while after quitting smoking, CYP1A2*1F (p = 0.017) and contraceptives(p = 0.05) did. No influence of CYP1A2 polymorphisms on the inducibilityof CYP1A2 was observed. Conclusion: Higher CYP1A2 activity wasmeasured in smokers, but with a large interindividual variability of its inductionby smoking. Careful clinical management with the help of therapeutic drug monitoringis therefore needed for patients receiving drugs which are metabolized byCYP1A2, who stop or start smoking. Unidentified genetic variations in theCYP1A2 gene and/or in other genes controlling CYP1A2 activity and other environmentalfactors could be responsible of the observed differences in CYP1A2enzymatic activity and inducibility.

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BACKGROUND: Polymorphisms in IFNL3 and IFNL4, the genes encoding interferon λ3 and interferon λ4, respectively, have been associated with reduced hepatitis C virus clearance. We explored the role of such polymorphisms on the incidence of cytomegalovirus (CMV) infection in solid-organ transplant recipients. METHODS: White patients participating in the Swiss Transplant Cohort Study in 2008-2011 were included. A novel functional TT/-G polymorphism (rs368234815) in the CpG region upstream of IFNL3 was investigated. RESULTS: A total of 840 solid-organ transplant recipients at risk for CMV infection were included, among whom 373 (44%) received antiviral prophylaxis. The 12-month cumulative incidence of CMV replication and disease were 0.44 and 0.08 cases, respectively. Patient homozygous for the minor rs368234815 allele (-G/-G) tended to have a higher cumulative incidence of CMV replication (subdistribution hazard ratio [SHR], 1.30 [95% confidence interval {CI}, .97-1.74]; P = .07), compared with other patients (TT/TT or TT/-G). The association was significant among patients followed by a preemptive approach (SHR, 1.46 [95% CI, 1.01-2.12]; P = .047), especially in patients receiving an organ from a seropositive donor (SHR, 1.92 [95% CI, 1.30-2.85]; P = .001), but not among those who received antiviral prophylaxis (SHR, 1.13 [95% CI, .70-1.83]; P = .6). These associations remained significant in multivariate competing risk regression models. CONCLUSIONS: Polymorphisms in the IFNL3/4 region influence susceptibility to CMV replication in solid-organ transplant recipients, particularly in patients not receiving antiviral prophylaxis.

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Summary The proinflammatory cytokine macrophage migration inhibitory factor (MIF) has emerged as a central mediator of inflammation and innate immune defense against infections. MIF has been shown to play an important role in the pathogenesis of infectious diseases like sepsis, tuberculosis and autoimmune inflammatory diseases, such as arthritis, inflammatory bowel disease and asthma. Two functional polymorphisms of the MIF gene promoter, a five to eight CATT repeat microsatellite at position -794 and a G/C SNP at position -173, have been associated with increased susceptibility to or severity of autoimmune inflammatory diseases like arthritis, colitis and atopy. The aim of this thesis was to define whether, and if so by which mechanisms, MIF gene polymorphisms influence the susceptibility to or the outcome of one of the most severe and one of the most prevalent infectious diseases: meningococcal sepsis and tuberculosis, respectively. The results of the comparison between 1106 patients suffering from severe meningococcal infections and 434 healthy volunteers showed that carriers of the CATT5-5 genotype were protected from meningococcemia. A transmission disequilibrium test involving 106 families confirmed this association. At baseline and after stimulation with Neisseria meningitidis, the CATT5 MIF promoter drove lower transcriptional activity than the CATT6 or CATT7 alleles in human monocytic cells and whole blood of CATT5-5 healthy individuals tended to produce less MIF than whole blood of CATT6-6 individuals. Beyond, we describe several new MIF gene polymorphisms in Africans. Genotyping the CATT microsatellite and the -173*G/C SNP revealed great genetic diversity in six African ethnic groups. Comparing 471 African tuberculosis cases and 932 matched healthy controls, we observed ethnicity dependent associations of the -173*G/C and the CATT5-8 with susceptibility to or severity of tuberculosis, but confirmation in larger cohorts ìs needed. In conclusion, we report that homozygous carriage of a low expression allele of the MIF gene protects from meningococcal disease. These results support the concept that analyses of MIF genotypes in patients with sepsis may help to classify patients into risk categories and to identify those patients who may benefit from anti-MIF therapeutic strategies.

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BACKGROUND: Leprosy is characterized by a spectrum of clinical manifestations that depend on the type of immune response against the pathogen. Patients may undergo immunological changes known as "reactional states" (reversal reaction and erythema nodosum leprosum) that result in major clinical deterioration. The goal of the present study was to assess the effect of Toll-like receptor 2 (TLR2) polymorphisms on susceptibility to and clinical presentation of leprosy. METHODS: Three polymorphisms in TLR2 (597C--&gt;T, 1350T--&gt;C, and a microsatellite marker) were analyzed in 431 Ethiopian patients with leprosy and 187 control subjects. The polymorphism-associated risk of developing leprosy, lepromatous (vs. tuberculoid) leprosy, and leprosy reactions was assessed by multivariate logistic regression models. RESULTS: The microsatellite and the 597C--&gt;T polymorphisms both influenced susceptibility to reversal reaction. Although the 597T allele had a protective effect (odds ratio [OR], 0.34 [95% confidence interval {CI}, 0.17-0.68]; P= .002 under the dominant model), homozygosity for the 280-bp allelic length of the microsatellite strongly increased the risk of reversal reaction (OR, 5.83 [95% CI, 1.98-17.15]; P= .001 under the recessive model). These associations were consistent among 3 different ethnic groups. CONCLUSIONS: These data suggest a significant role for TLR-2 in the occurrence of leprosy reversal reaction and provide new insights into the immunogenetics of the disease.

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BACKGROUND: High baseline levels of IP-10 predict a slower first phase decline in HCV RNA and a poor outcome following interferon/ribavirin therapy in patients with chronic hepatitis C. Several recent studies report that single nucleotide polymorphisms (SNPs) adjacent to IL28B predict spontaneous resolution of HCV infection and outcome of treatment among HCV genotype 1 infected patients. METHODS AND FINDINGS: In the present study, we correlated the occurrence of variants at three such SNPs (rs12979860, rs12980275, and rs8099917) with pretreatment plasma IP-10 and HCV RNA throughout therapy within a phase III treatment trial (HCV-DITTO) involving 253 Caucasian patients. The favorable SNP variants (CC, AA, and TT, respectively) were associated with lower baseline IP-10 (P = 0.02, P = 0.01, P = 0.04) and were less common among HCV genotype 1 infected patients than genotype 2/3 (P<0.0001, P<0.0001, and P = 0.01). Patients carrying favorable SNP genotypes had higher baseline viral load than those carrying unfavorable variants (P = 0.0013, P = 0.029, P = 0.0004 respectively). Among HCV genotype 1 infected carriers of the favorable C, A, or T alleles, IP-10 below 150 pg/mL significantly predicted a more pronounced reduction of HCV RNA from day 0 to 4 (first phase decline), which translated into increased rates of RVR (62%, 53%, and 39%) and SVR (85%, 76%, and 75% respectively) among homozygous carriers with baseline IP-10 below 150 pg/mL. In multivariate analyses of genotype 1-infected patients, baseline IP-10 and C genotype at rs12979860 independently predicted the first phase viral decline and RVR, which in turn independently predicted SVR. CONCLUSIONS: Concomitant assessment of pretreatment IP-10 and IL28B-related SNPs augments the prediction of the first phase decline in HCV RNA, RVR, and final therapeutic outcome.