Association of two polymorphisms of the IL28B gene with viral factors and treatment response in 1,518 patients infected with hepatitis C virus

Background

Two nucleotide polymorphisms of the interleukin-28B (IL28B) gene, at rs8099917 and rs12979860, influence the response to interferon (IFN)-based therapies in patients infected with hepatitis C virus (HCV) of genotype 1. We aimed to investigate whether these polymorphisms showed complete linkage in Japanese patients.

Methods

A total of 1,518 Japanese patients infected with HCV were genotyped for the two IL28B loci, and the two sets of genotypes were compared.

Results

TT at rs8099917 and CC at rs12979860 were detected in 77.7 and 76.8%, respectively, of the 1,518 patients and TG/GG and CT/TT were detected in 22.3 and 23.2%. These two sets of IL28B genotype stood in strong linkage disequilibrium (r ²?=?0.98). Discordance between the two IL28B polymorphisms occurred in 16 (1.1%) patients, and 13 (0.9%) of them possessed IFN-sensitive TT at rs8099917 and IFN-resistant CT at rs12979860. Three of these 13 patients had HCV of genotype 1b and had received pegylated-interferon and ribavirin, and none of them gained a sustained virological response. At rs8099917, IFN-resistant TG/GG were more frequent in patients infected with HCV of genotype 1 than in those infected with HCV of genotype 2 [258/1,046 (24.7%) vs. 75/441 (17.0%), p?=?0.001]. The response to pegylated-interferon/ribavirin in 279 patients who were infected with HCV-1 and the response to IFN monotherapy in 361 patients who were infected with HCV-1 , was higher in those with TT than in those with TG/GG at rs8099917, as well as being higher in those with CC than in those with CT/TT at rs12979860 (p?Conclusions Linkage disequilibrium between two IL28B polymorphisms at rs8099917 and rs12979860 is strong in Japanese HCV patients, but there are some discrepancies between the two sets of genotypes.     

慢性丙型肝炎患者病毒基因型与IL-28B基因型分布

目的：了解慢性丙型肝炎患者白细胞介素-28B（IL-28B）基因型多态性分布的特点及其临床意义。方法在27例慢性丙型肝炎患者,分离外周血细胞DNA,采用IPLEX Gold法检测宿主IL-28B基因多态性;分析患者IL-28B基因型与血清丙型肝炎病毒（HCV）基因型、HCV RNA载量和肝功能指标的相关性。结果在27例慢性丙型肝炎患者中,感染HCV基因1型1例（3.7%）,1b基因型7例（25.9%）,其它基因型19例（19/27,70.4%）;在IL-28B基因型中,rs12979860 CC基因型、rs12980275 AA基因型及rs8099917 TT基因型共24例（88.9%）,而IL28B rs12979860 CT基因型、rs12980275 GA基因型和rs8099917 GT基因型共3例（11.1%）;在HCV基因1型或1b型感染者中,IL28B rs12979860 CC基因型、rs12980275 AA基因型和rs8099917 TT基因型占62.5%（5/8）,而HCV其他基因型感染者IL28B rs12979860 CC基因型、rs12980275 AA基因型和rs8099917 TT基因型占100%（19/19）;HCV基因1型或1b型感染者与HCV其他基因型感染者比,其IL28B rs12979860位点、rs12980275位点和rs8099917位点基因型分布有显著性差异（P＆lt;0.01）;IL-28B基因多态性分布与患者血清HCV RNA载量或肝功能指标的变化无显著性相关。结论本组慢性丙型肝炎患者HCV基因型大多为非1型;大多数感染者IL-28B基因为rs12979860 CC、rs12980275 AA和rs8099917 TT基因型。     

Distribution of IL28B Genotypes in Iranian Patients with Chronic Hepatitis C and Healthy Individuals

Background

IL28B polymorphism is recognized as one of the most prominent predictors of hepatitis C spontaneous and treatment-induced clearance. Interestingly, the favorable genotypes of IL28B are found to be more frequent in Asian ethnicity than Caucasian and African populations, respectively. A few studies reported that there is a mysterious association between the IL28B polymorphism and the hepatitis C virus (HCV) genotype in patients with chronic hepatitis C but they did not give any reason for this phenomenon.

Objectives

The foremost purpose of this study was to compare the distribution of IL28B genotypes between Iranian healthy individuals and patients with chronic hepatitis C.

Patients and Methods

In this study, 921 patients with chronic hepatitis C and 142 healthy individuals were included. The IL28B rs12979860 and rs8099917 polymorphisms were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

Results

The frequency of IL28B rs12979860 CC, CT, and TT genotypes in chronic hepatitis C patients was 38%, 48.8%, and 13.2% and in healthy individuals was 43.7%, 48.6%, and 7.7%. Also, the frequency of IL28B rs8099917 TT, GT, and GG genotypes in chronic hepatitis C patients was 58.3%, 37.1%, and 4.6% and in healthy individuals was 64.1%, 32.4% and 3.5%. The differences in the distribution of IL28B rs12979860 and rs8099917 genotypes between patients with chronic hepatitis C and healthy individuals were not statistically significant. When we compared the distribution of IL28B genotypes between the healthy group and the HCV infected patients by HCV genotype, we found 9.8% higher frequency of rs12979860 CC genotype in the healthy individuals than HCV genotype 1 infected patients (P = 0.03) however there was no significant difference in the distribution of rs12979860 genotypes between the healthy and HCV genotype 3 infected groups (P = 0.46).

Conclusions

It seems that the impact of IL28B polymorphism on the spontaneous clearance of HCV genotype 1 is more prominent than HCV genotype 3 which results in the observation of higher rs12979860 C allele frequency in chronic hepatitis C patients with HCV genotype 3 than HCV genotype 1.     

Genetic polymorphism of IL28B in hepatitis C‐infected haemophilia patients in Israel

Single‐nucleotide polymorphisms (SNPs) near the IL28B gene were identified as major predictors of treatment response (sustained virologic response – SVR) and spontaneous clearance of HCV. Haemophilia patients have the highest prevalence of HCV, and are a unique target for genetic studies. The Israeli population is ethnically heterogeneous; therefore, genetic variability is anticipated. To determine the IL28B haplotypes in HCV‐infected haemophilia patients and association with SVR and spontaneous viral clearance. IL28B polymorphism at SNPs rs12979860 and rs8099917 was determined in sera obtained from 130 HCV‐infected haemophilia patients. The frequency of the various haplotypes was analysed according to treatment response, spontaneous HCV clearance, viral load and degree of fibrosis. The CC haplotype at SNP rs12979860 was found in 31% of patients, whereas the TT genotype at SNP rs8099917 was detected in 57% of cases. SVR was achieved in 70% of patients carrying the CC haplotype (P = 0.0196 vs. CT/TT), and 50% of the TT genotype at SNP rs8099917 (P = 0.0227 vs. TG/GG). Thirty‐five percent of patients carrying the CC haplotype and 26% with the TT genotype at SNP rs8099917 showed spontaneous clearance of HCV infection (P = 0.00262 vs. CT/TT; and P = 0.00371 vs. TG/GG respectively). The C‐allele frequency was exceptionally high (71%) in immigrants from the Asian republics of Russia. In HCV‐infected haemophilia patients, SVR was more commonly achieved among patients who had the CC ( rs12979860 ) or TT ( rs8099917 ) genotype. Likewise, patients who possess harbour the CC or TT genotypes were more likely to clear HCV infection spontaneously. A unique distribution of the CC genotype was observed in some ethnic groups.     

IL28B genetic variants and gender are associated with spontaneous clearance of hepatitis C virus infection

Summary. Single nucleotide polymorphisms (SNPs) near the IL28B gene have been shown to be associated with response to treatment for chronic hepatitis C and also with spontaneous clearance of hepatitis C virus (HCV) infection. We analysed the association between IL28B genetic variants and spontaneous clearance of HCV infection in 376 HCV‐infected Chinese paid plasma donors. Genotyping of eight SNPs near the IL28B region was performed by the iPLEX system (MassARRAY^® SNP Genotyping; Sequenom) in all donors, and sequencing was performed on all 80 donors who cleared HCV and on 160 of 296 donors who did not clear HCV to validate the genotypes. Eighty (21.3%) donors spontaneously cleared HCV. Four SNPs were significantly associated with spontaneous HCV clearance: rs8099917 TT (vs GT), rs8105790 TT (vs CT), rs12980275 AA (vs AG) and rs10853728 CC (vs CG or GG) with OR (95% CI) 15.27 (2.07–112.50), 14.88 (2.02–109.72), 7.92 (1.88–33.32) and 2.32 (1.22–4.42) respectively. No association between the other four IL28B SNPs including rs12979860 and spontaneous HCV clearance was found. Women had a higher rate of spontaneous HCV clearance than men [56/213 (26.3%) vs 24/163 (14.6%), P = 0.007], and this was true even after stratification for IL28B genotypes with OR of 1.9–2.2 among those with favourable genotypes. Our results confirmed that IL28B polymorphism is associated with spontaneous clearance of HCV in Chinese subjects, but the SNPs that predict HCV clearance in Chinese subjects were different from those reported in Caucasians. Women were more likely to clear HCV infection regardless of IL28B genotypes.     

Interleukin 28B-related polymorphisms: A pathway for understanding hepatitis C virus infection?

AIM:To analyze the role of rs12979860 and rs8099917polymorphisms in hepatitis C virus(HCV)genotype 1infection of Brazilians.METHODS:A total of 145 adult patients diagnosed with genotype 1 chronic hepatitis C(CHC)who had completed a 48-wk regimen of pegylated-interferonα-2a or-2b plus ribavirin combination therapy were recruited from six large urban healthcare centers and199 healthy blood donors(controls)from a single site between January 2010 and January 2012.Data on the patients’response to treatment was collected.Polymerase chain reaction-restriction fragment length polymorphism genotyping of the interleukin(IL)28B gene fragment encompassing the single nucleotide polymorphisms(SNPs)rs12979860(C/T)and rs8099917(T/G)was carried out for 79 of the CHC patients and 199 of the controls.Bi-directional amplicon sequencing of the two SNPs was carried out for the remaining 66 CHC patients.RESULTS:SNP rs12979860 genotyping was successful in 99.5%of the controls and 97.2%of the CHC patients,whereas the SNP rs8099917 genotyping was successful in 95.5%of the controls and 100%of the CHC patients.The genotype and allele distributions for both rs12979860 and rs8099917 were significantly different between the control and CHC patient groups,with significantly higher genotype frequencies of CC and TT in the controls(P=0.037 and 0.046,respectively)and of TT and GG in the CHC patients(P=0.0009and 0.0001,respectively).Analysis of the CHC patients who achieved sustained virological response(SVR)to treatment(n=55)indicated that the rs12979860 C allele and CC genotype were predictors of SVR(P=0.02).No significant correlation was found between rs8099917 genotypes and treatment response,but carriers of the T allele showed significantly higher rates of SVR(P=0.02).Linkage disequilibrium analysis of the group that achieved SVR showed a significant association between rs12979860 and rs8099917(P=0.07).CONCLUSION:The higher allele frequency of rs12979860 C and rs8099917 T observed in non-HCVinfected individuals may indicate a potential pro     

Renin angiotensin system polymorphisms in patients with metabolic syndrome (MetS)

BackgroundThe genes associated with hypertension could be genetic risk factors for metabolic syndrome (MetS).AimTo determine the frequency of M235T and T174M-AGT, I/D-ACE and A1166C-AGTR1 in hypertensive patients with MetS and to evaluate the relationship between these polymorphisms and central obesity and dyslipidemia, respectively.Materials and methodsWe performed AGT, AGTR1 and ACE genotyping in 56 hypertensive women (24 with MetS) and 71 normotensive women using PCR-RFLP methods and PCR, respectively.ResultsHypertensive patients carrying the mutated TT235, MM174 and DD genotypes had an 1.53 (p = 0.56), 1.78 (p = 0.52) and 1.28 (p = 0.78)-fold increased risk to develop MetS. Hypertensive carriers of both mutated TT235 and MM174 or TT235 and D/D or TT235 and CC + AC genotypes had an 8.15 (p = 0.04), 4.83 (p = 0.04) and 10.53 (p = 0.05)-fold increased risk to develop MetS. Hypertensive patients with MetS and TT, D/D or CC genotypes had higher body mass index compared to hypertensive patients without MetS (p ≤ 0.05 for all the genotypes). Hypertensive patients with MetS and TT235, MM174, D/D or CC1166 genotypes had higher triglyceride levels, lower HDL-cholesterol levels and higher waist circumference compared to hypertensive patients without MetS (p ≤ 0.05, except for the association between CC1166 and HDL-cholesterol level).ConclusionsThe effect of the T174M, I/D and A1166C polymorphisms on MetS may depend on the M235T polymorphism. Among hypertensive subjects with MetS, the presence of TT235, MM174, DD and CC1166 genotypes could be a risk factor for central obesity and dyslipidemia.     

Interleukin-28B (IL-28B) single-nucleotide polymorphisms and interferon plus ribavirin treatment outcome in Italian chronically HCV-infected patients

Summary. To determine the single or combined effect of both rs12979860 and rs8099917 SNPs on HCV treatment response, these variants were genotyped in samples from a cohort of 170 patients infected with different HCV genotypes (HCVGT). The favourable rs12979860 CC genotype was found only in patients with sustained or rapid virological responses (SVR/RVR) and at significantly high proportions in HCVGT1/4 SVR patients. A significant association was also found between the rs8099917 TT genotype and SVR in both HCVGT1/4 and HCVGT2/3 groups of patients. In contrast, we found that there was significantly more of the rs8099917 GG genotype in nonresponders (NR) than in SVR patients which suggests a good association of the minor homozygote GG with the lack of treatment response. The combination of rs12979860/rs8099917 CC/TT favourable genotypes was found only in SVR patients and matched the frequency observed for their rs12979860 CC genotypes alone. By contrast, the inverse unfavourable correlate rs12979860/rs8099917 TT/GG genotype was seen more in NR than in SVR patients as observed for the single GG genotype. This study confirms the impact of both rs12979860 and/or rs8099917 IL-28B SNPs on treatment-induced clearance of HCV-RNA and demonstrates that the rs12979860 CC genotype is stronger than rs8099917 TT genotype in predicting a positive treatment response in HCVGT1/4 patients. The unfavourable rs8099917 GG genotype seems to be more important in predicting the failure of treatment response independently from HCV genotype.     

Combined effects of different interleukin-28B gene variants on the outcome of dual combination therapy in chronic hepatitis C virus type 1 infection

In patients with chronic hepatitis C virus (HCV) infection, several variants of the interleukin-28B (IL28B) gene have been shown to correlate significantly with a sustained virologic response (SVR). Recent evidence shows that determination of one single IL28B polymorphism, rs12979860, is sufficient for predicting treatment outcome. We examined whether the combined determination of the IL28B single-nucleotide polymorphisms (SNPs), rs12979860, rs8099917, rs12980275, and rs8103142, might improve the prediction of SVR in patients with HCV. In the study cohort, 54% of 942 patients with chronic HCV type 1 infection had SVR. The IL28B SNPs, rs12979860CC and rs8099917TT, correlated significantly with SVR (68% and 62%). The SNPs, rs12980275 and rs8103142, were in strong linkage disequilibrium with rs12979860 and were not included in further analysis. In homozygous carriers of the rs12979860 responder allele C, additional genotyping of the rs8099917 SNP had no effect on response prediction, whereas in carriers of the rs12979860 nonresponder allele, the rs8099917 SNP improved the response prediction. In heterozygous carriers of the rs12979860 nonresponder T allele, SVR rates were 55% in the presence of the rs8099917TT genotype and 40% in patients carrying the rs8099917 TG or GG genotype. Analysis of an independent confirmation cohort of 377 HCV type 1-infected patients verified the significant difference in SVR rates between the combined genotypes, rs12979860CT/rs8099917TT and rs12979860CT/rs8099917TG (38% versus 21%; P = 0.018). Conclusion: Treatment outcome prediction could not be improved in homozygous carriers of the IL28B rs12979860 C responder allele by the additional determination of the rs8099917 SNP. There is evidence that a significant proportion of heterozygous carriers of the rs12979860 T nonresponder allele can profit with respect to SVR prediction by further determination of the rs8099917 SNP. (HEPATOLOGY 2012;55:1700-1710).     

IL28B polymorphisms predict response to therapy among chronic hepatitis C patients with HCV genotype 4

Summary. Genetic polymorphisms near IL28B are associated with spontaneous and treatment‐induced clearance of hepatitis C virus (HCV). Our objective was to assess the predictive value of IL28B polymorphisms in the treatment of chronic hepatitis C of patients with HCV genotypes 4, for which data are currently limited. We analysed the association of IL28B polymorphisms with the virological response to treatment among 182 naïve chronic hepatitis C patients with HCV genotype 4, all from Syria. Associations of alleles with the response patterns were evaluated by univariate analysis and multivariate logistic regression, accounting for all relevant covariates. Sustained virological response (SVR) was achieved in 26% of rs8099917 TG/GG carriers compared with 60% of TT carriers (P < 0.0001) and 35% of rs12979860 CT/TT carriers compared with 62% of CC carriers (P = 0.0011). By multivariate analysis, the association between rs8099917 and SVR remained significant (OR = 0.19, 95% CI 0.07–0.50, for TG/GG vs TT, P = 0.0007), with the only significant covariate being advanced fibrosis (OR = 0.13, 95% CI 0.04–0.37, P = 0.0002). In conclusion, IL28B polymorphisms are the strongest predictors of response to therapy among chronic hepatitis C patients with HCV genotype 4.     

Association of IL28B Polymorphisms With the Response to Peginterferon Plus Ribavirin Combined Therapy in Polish Patients Infected With HCV Genotype 1 and 4

Background

Three single nucleotide polymorphisms (SNPs) near interleukin-28B (IL-28B) gene were shown to be highly associated with treatment response (SVR) in patients with chronic hepatitis C virus (HCV) infection. There is limited data about the role of single and combined IL-28B polymorphisms in HCV-infected Polish population.

Objectives

This study''s aim was to determine predictability of three IL-28B gene polymorphisms and other known prognostic factors on the treatment response in HCV genotype 1 and 4 infected Polish patients. The effect of IL-28B polymorphisms on therapy was also compared with other known prognostic factors.

Patients and Methods

We genotyped IL-28B polymorphisms (rs12979860, rs12980275 and rs8099917) by polymerase chain reaction-based restriction fragment length polymorphism assay in a group of 293 patients from which a selected cohort of 174 treatment-naiev patients underwent treatment.

Results

We showed that rs12979860 CC [odds ratio (OR) = 4.6, P < 0.001], rs12980275 AA (OR = 2.9, P = 0.002) and rs8099917 TT (OR = 2.2, P = 0.016) genotypes were associated with successful treatment compared to the rs12979860 CT-TT, rs12980275 AG-GG and rs8099917 TG-GG, respectively. Patients bearing of IL-28B profile including the three favourable genotypes do not have much chance of a recovery (OR = 3.4, P = 0.002). Except for IL-28B polymorphisms, there was no association of SVR with any other pretreatment clinical data in analyzed group. The correlation of SNPs with other host and viral factors revealed association of favorable genotypes of IL-28B markers with high levels of alanine aminotransferase and baseline HCV viral load.

Conclusions

IL-28B polymorphisms were the strongest pretreatment predictors of response to pegylated interferon and ribavirin in Polish patients chronically infected with HCV genotype 1 and 4. This study confirm the strongest impact of IL-28B rs12979860 on SVR, nevertheless rs12980275 AA seems to be more important than rs8099917 TT in predicting positive treatment response.     

Role of IL28B and inosine triphosphatase polymorphisms in the treatment of chronic hepatitis C virus genotype 6 infection

IL28B and inosine triphosphatase (ITPA) polymorphisms are able to predict treatment response and degree of ribavirin‐related anaemia, respectively, in the treatment of chronic hepatitis C virus (HCV) infection. However, their roles in the treatment of chronic HCV genotype 6 remain undetermined. Sixty patients who were infected with HCV genotype 6 were commenced on 48 weeks of combination pegylated interferon and ribavirin therapy. Response to therapy, profiles of haemoglobin changes and platelet counts during therapy and their associations with IL28B rs8099917 and ITPA rs1127354 polymorphisms were analysed. The overall sustained virologic response (SVR) rate was 91.7%. 18 patients (30.0%) required a reduction in ribavirin dosage. The distribution of IL28B rs8099917 TT/TG genotypes and ITPA rs1127354 CC/CA genotypes were in Hardy–Weinberg equilibrium. IL28B rs8099917 TT genotype, when compared to TG genotype, was significantly associated with an increased SVR rate (96.2% and 62.5%, respectively) and was the only clinical parameter that predicted SVR (P = 0.014). The same significant association was observed when analysing allelic frequencies (T vs G, P = 0.001). ITPA rs1127354 CA genotype, when compared to CC genotype, was associated with lesser degree of anaemia throughout therapy (P < 0.05 for all time points). ITPA polymorphisms showed no association with changes in platelet count throughout therapy (P > 0.05 for all time points) and was not associated with SVR (P = 0.640). In chronic HCV genotype 6 infection, IL28B polymorphisms were associated with response to therapy. ITPA polymorphisms influenced the degree of anaemia but not thrombocytopenia during therapy.     

汉族人群乙型肝炎病毒感染者外周血IL-28B基因多态性研究*

目的 分析乙型肝炎病毒（HBV）感染者外周血IL-28B基因型和等位基因频率分布,并探讨其与疾病病程和进展的关系。方法 本研究纳入江苏籍汉族健康人群145例和453例HBV感染者,后者包括无症状HBV携带者（ASC）45例,慢性乙型肝炎患者（CHB）181例,肝硬化（LC）患者69例,肝细胞癌（HCC）患者79例,乙型肝炎肝衰竭（LF）患者79例,采用PCR法和直接测序法检测外周血IL-28B基因rs12979860和rs8099917多态性位点。采用Pearson x²检验对IL-28B rs8099917与rs12979860位点进行Hardy-Weinberg平衡检验,计量资料以（x±s）表示,计数资料采用例数表示。应用SPSS 17.0软件进行方差分析、x²检验和Binary Logistic回归分析。结果 IL-28B基因rs12979860位点有CC、CT和TT 3个基因型,LF患者CC型和C等位基因频率分别为96.2%和98.1%,显著高于健康人群的87.6%和93.1%（OR=0.257,95%CI=0.068~0.973,P=0.045;OR=0.255,95%CI=0.070~0.928,P=0.038）;IL-28B基因rs8099917位点有TT 、TG和GG 3个基因型,LC患者TT型和T等位基因频率分别为92.8%和96.4%,显著高于健康人群的86.2%和92.4%（OR=0.288,95%CI=0.087~0.948,P=0.041;OR=0.299,95%CI=0.096~0.926,P=0.036）。结论 江苏地区汉族人群IL-28B基因多态性与HBV感染后不同疾病表型相关,IL-28B基因rs12979860的C等位基因和IL-28B基因rs8099917的T等位基因可能是HBV感染后病情进展的影响因素。     

Development and Validation of a Simple, Rapid and Inexpensive PCR-RFLP Method for Genotyping of Common IL28B Polymorphisms: A Useful Pharmacogenetic Tool for Prediction of Hepatitis C Treatment Response

Background

In 2009, 3 genome-wide association studies implicated IL28B single-nucleotide polymorphisms (SNPs) as the strongest genetic pretreatment predictor of sustained virological response (SVR) in hepatitis C infection. Recently, the American Association for the Study of Liver Diseases (AASLD) and the European Association for the Study of the Liver (EASL) included IL28B testing in their guidelines.

Objectives

The main aim of this study was to develop and validate a simple, rapid, and inexpensive polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method for genotyping of common IL28B polymorphisms (rs12979860 and rs8099917).

Patients and Methods

Two methods were developed to genotype common IL28B polymorphisms: 1) PCR-sequencing as a reference method and 2) PCR-RFLP as a rapid and inexpensive method. Both polymorphisms were genotyped in 104 Iranian hepatitis C patients by both methods simultaneously. To validate the PCR-RFLP method, the PCR-RFLP genotyping results should be 100% concordant with the PCR-sequencing results.

Results

Genotyping of rs12979860 and rs8099917 by PCR-RFLP was concordant with PCR-sequencing in 104 (100%) individuals. The analytical sensitivity and specificity of the PCR-RFLP method for genotyping of both SNPs are 100%. Among these 104 patients with chronic hepatitis C, the frequency of the rs12979860 CC, CT and TT genotypes were 40.4%, 47.1% and 12.5% and the frequency of the rs8099917 TT, GT and GG genotypes were 59.6%, 35.6% and 4.8%, respectively. Also, three IL28B haplotypes (rs12979860-rs8099917) were found among our patients including C-T, T-G and T-T with 63.9%, 22.6% and 13.5% frequency, respectively. C-G haplotype was absent in all of our patients.

Conclusions

We have developed a validated, fast, and simple PCR-RFLP method for genotyping of common IL28B SNPs that is more cost-effective than sequencing.     

Genetic variation in interleukin-28B predicts SVR in hepatitis C genotype 1 Argentine patients treated with PEG IFN and ribavirin

Background and aims. Genetic variations in the interleukin 28B (IL28B) gene have been associated with viral response to PEG-interferon-a/ribavirin (PR) therapy in hepatitis C virus (HCV) genotype 1 infected patients from North America, Europe and Asia. The importance of these IL28B variants for Argentine patients remains unknown.Material and methods. IL28B host genotypes (rs8099917 and rs12979860) were determined in a population of Argentine patients with European ancestry. Results were analyzed looking for their association with sustained virologic response (SVR) to PR therapy and compared with other baseline hosts’ biochemical, histological and virological predictors of response.Results. We studied 102 patients, 60% were men, and 40% of them were rs8099917 TT and 18% rs12979860 CC. Mean baseline serum HCV RNA was 1.673.092 lU/mL and mean F score was: 2.10 ± 1.18 (21% cirrhotic). SVR rate was higher in rs8099917 TT genotypes (55%) when compared to GT/GG (25%) (p = 0.002) and in rs1512979860 CC (64%) than in CT/TT (30%) (p = 0.004). The univariate analysis showed that rs8099917 TT (OR 3.7; 95 %CI 1.5-8.7; p = 0.002), rs12979860 CC (OR 4.6; 95%CI 1.5-13.7; p = 0.006), low viral load (OR 4.6; 95°% CI 1.7-12.6; p = 0.002) and F0-2 (OR 8.5; 95°% CI 2.3-30.6; p = 0.001) were significantly associated with SVR. In the multivariate analysis, rs12979860 CC, rs8099917 TT, viral load < 400.000 IU/mL and F0-2 were associated with SVR rates (p = 0.029, p = 0.012, p = 0.013 and p = 0.004, respectively).Conclusion. IL28B host genotypes should be added to baseline predictors of response to PR therapy in Latin American patients with European ancestry.     

江苏地区汉族人群白细胞介素28B基因多态性与丙型肝炎易感性的关系

目的探讨江苏地区汉族人群白细胞介素(IL)28B基因多态性分布及其与丙型肝炎易感性的关系。方法选取2011年南京市第二医院就诊的丙型肝炎患者88名,体检中心健康体检的健康人群100例。应用聚合酶链式反应(PCR)和直接测序法检测丙型肝炎患者和健康人群IL-28B rs8099917、rs12979860、rs12980275、rs8113007和rs12972991位点的单核苷酸多态性(SNP),并统计分析这些位点的基因型和等位基因在两种不同人群中分布的差异。采用Pearsonχ2检验进行分析,计算Hardy-Weinberg遗传平衡以判断样本的代表性。结果两者间性别和年龄差异均无统计学意义(P=0.92、0.28),在检测人群中IL-28B基因5个位点的主要基因型分别是TT、CC、AA、AA、AA;丙型肝炎患者IL-28B基因SNP位点与健康人群在基因型(χ2=0.31、0.50、0.60、0.15、0.07,P均0.05)和等位基因(χ2=0.29、0.48、0.56、0.14、0.07,P均0.05)分布上差异均无统计学意义。结论 IL-28B的SNPs位点(rs8099917、rs12979860、rs12980275、rs8113007、rs12972991)可能与江苏省汉族人群丙型肝炎易感性无关。     

IL28B polymorphisms influence stage of fibrosis and spontaneous or interferon-induced viral clearance in thalassemia patients with hepatitis C virus infection

Background

Polymorphisms in the interleukin-28B are important determinants in the spontaneous and drug-induced control of hepatitis C virus infection.

Design and Methods

We assessed the association of rs8099917 and rs12979860 polymorphisms with spontaneous viral clearance, severity of liver fibrosis, and response to interferon-monotherapy in 245 thalassemia major patients with hepatitis C virus infection.

Results

Ninety-eight patients (40%) had a spontaneous viral clearance while 147 patients (60%) developed a chronic infection. Spontaneous viral clearance was more frequent among patients with the T/T genotype of rs8099917 polymorphism (OR 2.130; P=0.008) or C/C genotype of rs12979860 polymorphism (OR 2.425; P=0.001). During observation, 131 patients with chronic infection underwent a liver biopsy; age (OR 1.058; P=0.01) G/T or G/G genotypes of rs8099917 polymorphism (OR 3.962; P=0.001), and C/T or T/T genotypes of rs12979860 polymorphism (OR 3.494; P=0.005) were associated with severe liver fibrosis, independent of liver iron concentration. Finally, T/T genotype of rs8099917 polymorphism (OR 3.014; P=0.03) or C/C genotype of rs12979860 polymorphism (OR 3.285; P=0.01), age (OR 0.902; P=0.001), female gender (OR 3.418; P=0.01) and 2 or 3 virus C genotypes (OR 4.700; P=0.007) were independently associated with sustained virological response in 114 patients treated with alpha-interferon.

Conclusions

Polymorphisms in the interleukin-28B are associated with the control of hepatitis C virus infection in thalassemia major patients, and understanding allelic patterns has an important role in determining prognosis and therapeutic management.     

Interferon-λ polymorphisms and response to pegylated interferon in Iranian hepatitis C patients

AIM: To evaluate the efficacy of pegylated interferon in Iranian chronic hepatitis C patients in relation to interferon-λ(IFNL) polymorphisms. METHODS: This study enrolled patients with chronic hepatitis C referred to the Tehran Blood Transfusion Hepatitis Clinic in 2011. Patients were included in the study if they had no concomitant hepatic illness, were negative for human immunodeficiency virus antibodies, and had no prior history of treatment with any type ofpegylated interferon. Patients were treated with 180 μg pegylated interferon alpha-2a(Pegaferon#174;) weekly and 800-1200 mg ribavirin daily for 24 or 48 wk depending on weight and hepatitis C virus(HCV) genotype. Blood samples were collected from patients to obtain DNA for determination of IFNL rs12979860 and rs8099917 polymorphisms. The virologic response in patients was then evaluated and compared between the different IFNL genotypes.RESULTS: A total of 152 patients with a mean age of 41.9 ± 10.0 years were included in the study, of which 141/152 were men(92.8%). The most frequent HCV genotype was type-1, infecting 93/152(61.2%) patients. Sustained virologic response(SVR) was achieved in 81.9% of patients with HCV genotype-1 and 91.1% of patients with HCV genotype-3. Treatment success was achieved in 91.2%(52/57) of patients with the IFNL rs12979860 CC genotype and 82.1%(78/95) in those with other genotypes. Similar treatment response rates were also observed in patients with rs8099917 TT(39/45; 86.7%) and non-TT(61/68; 89.7%) genotypes. Univariate analyses identified the following factors which influenced treatment response for inclusion in a multivariate analysis: age, HCV RNA level, stage of liver fibrosis, rs12979860 CC genotype, and aspartate transaminase level. A logistic regression analysis revealed that only the rs12979860 CC genotype was significantly associated with achievement of SVR(OR = 6.2; 95%CI: 1.2-31.9; P = 0.03).CONCLUSION: The rs12979860 CC genotype was associated with SVR in patients receiving pegylated interferon plus ribavirin, however, the SVR rate in other rs12979860 genotypes was also relatively high.     

Single nucleotide polymorphisms of the IL28B and sustained virologic response of patients with chronic hepatitis C to PEG-interferon/ribavirin therapy: A meta-analysis: Meta-analysis of IL28B

Background

Hepatitis C is a global health problem and represents a major cause of liver disease and socioeconomic burden. Effective antiviral therapy may prevent these complications, but the current treatment for patients with chronic hepatitis C virus (HCV) infection does not produce sustained virologic response. Therefore, identification of the determinants of response to treatment is a high priority. A number of host and viral factors have been associated with treatment outcomes.

Objectives

To assess the associations of single nucleotide polymorphisms (SNP) of the IL28B and sustained virologic response (SVR) of patients with chronic hepatitis C to PEG-interferon/ribavirin therapy.

Materials and Methods

We searched PubMed, Medline and Cochrane Library, and found 7 eligible papers involved in this study. Then we performed a meta-analysis comparing the SVR rate at SNP of the IL28B in individuals with PEG-interferon/ribavirin therapy. Meanwhile, the SVR rate between different races and HCV genotypes was studied.

Results

The sustained virologic response rate was higher in patients with the rs12979860 CC and rs8099917 TT alleles in the IL28B SNP, comparing with the rs12979860 CT, or TT and rs8099917 TG or GG. Furthermore, a higher SVR was observed in the Caucasians than in Afro-Americans (OR = 3.85, 95% CI: 3.06-4.83); the percentage of rs12979860 TT genotype was lower in Caucasians (OR = 0.25, 95% CI: 0.20-0.31) and the percentage of rs12979860 CC genotype was higher in Caucasians than that of Afro-Americans (OR = 3.45, 95% CI = 2.68-4.44). Between different HCV genotypes, the SVR was much lower in those with HCV genotype 1 than those with genotype 2/3 (OR = 0.16, 95% CI: 0.11-0.24).

Conclusions

IL28B is significantly associated with response to PEG-interferon/ribavirin therapy of patients with chronic HCV infection. Both the rs12979860 and rs8099917 alleles could be used as independent predictors of the treatment response. The rs12979860 allele in particular, is more important from our study. The polymorphism even explains part the difference in response rate between different ethnic groups and HCV genotypes.     

Glucose tolerance and free fatty acid metabolism in adults with variations in TCF7L2 rs7903146

ObjectiveTCF7L2 variant rs7903146 is associated with increased risk for type 2 diabetes. We investigated the effect of TCF7L2 variant rs7903146 and glucose tolerance on free fatty acid (FFA) metabolism.Research Design and MethodsWe recruited 120 individuals, half homozygous for the major CC allele and half homozygous for the minor TT allele at rs7903146; each underwent a 2-h, 75 g oral glucose tolerance test (OGTT). Plasma glucose, insulin and free fatty acid concentrations were measured on blood collected before and during the OGTT.ResultsTotal FFA concentrations and percent FA species during OGTT were not different in CC and TT carriers when males and females were considered together. However, monounsaturated fatty acid (MUFA) concentrations and percentages were greater in TT than CC females during the OGTT. TT carriers with high HOMA-IR had significantly greater fasting FFA concentrations, lower disposition index (DI) and greater AUC of glucose than high HOMA-IR CC carriers, whereas no such differences were observed in the low HOMA-IR group. We found that fasting (826 ± 25 vs. 634 ± 22 μmol/L, P < 0.0001) and OGTT plasma FFA concentrations were greater in IGT than NGT subjects, and the difference remained after adjusting for sex, age, BMI, and genotype. Finally, IGT subjects had greater MUFA concentrations and percentages than NGT subjects during OGTT.ConclusionsDespite similar fasting insulin and glucose, fasting plasma FFA are greater in IGT than NGT adults. Insulin resistance and sex influence plasma FFA responses amongst carriers of the minor T allele of TCF7L2 rs7903146.