Association of rs12979860 and rs8099917 polymorphisms near IL28B with SVR in hepatic allograft recipients with HCV recurrence undergoing PEG-IFN/RBV therapy: a meta-analysis

MDR1 gene C3435T polymorphism in chronic hepatitis C patients

BACKGROUND

MDR1 is a highly polymorphic gene that encodes P-glycoprotein (P-gp). This protein anchor to the cell membrane and transports toxins, xenobiotic, chemicals, and drugs from the intracellular to extracellular and thus protect cells. Polymorphism of the MDR1 gene seems to be effective in gene expression and response to treatment. Since one of the main mechanisms of drug resistance is the removal of the drug from the cell by ATP-dependent efflux proteins, thus MDR1, single nucleotide polymorphism (SNP) C3435T can be used as a predictor for treatment outcomes.

METHODS

The peripheral blood-EDTA samples were collected from 71 patients with chronic hepatitis C. The total genomic DNA extraction was carried out. The PCR was performed for detection of the MDR1 gene in HCV patients and MDR1 gene polymorphism was genotyped by the PCR-RFLP method.

RESULTS

Out of 71 patients 52 (73.3%) were male, 19 (26.7%) female with mean age-min-max; 41.17 ± 8.3-(26-59). The distribution of MDR1 genotype in 48(67.6%) responders were CC 13 (27%), CT 34 (71%) and TT 1(2%), while MDR1 genotypes in 8 (11.3%) non responders were CC 2(25%), CT 1(12.5%) TT 5(62.5%) and in 15(21.1%) recurrence were 5 (33%) CC, 6 (40%) CT and 4 (27%) TT genotype. The patients with heterozygous CT (C3435T) genotype 34/48(71%) were found better response than non-responders with TT 5/8(62.5%) genotype (p < 0.05).

CONCLUSION

Our result reveals that 71% of the responders were CT genotypes (C3435T) and 62.5% of non-responders were TT genotype (T3435T). With aforementioned results, determination of different forms of SNPs in MDR1 gene should be considered as a predictor in the treatment of all chronic HCV patients. The homozygous TT genotype and high prevalence of T allele may be related to low antiviral response during combined therapy in treatment of chronic HCV patients.

Genetic variant of IL28B rs12979860, as predictive marker of interferon-based therapy in Pakistani population

Hepatitis C virus (HCV) genotypes and genetic variants of interleukin 28B (IL28B) are significantly associated with interferon plus ribavirin treatment of HCV infection. We investigated the distribution of HCV genotypes and single-nucleotide polymorphisms (SNPs) of IL28B (rs12979860 and rs8099917) in Pakistani population. IL28B genotyping was performed by allele-specific PCR and restriction fragment length polymorphism PCR in 140 chronic hepatitis C patients (CHC) and 120 healthy controls. HCV genotype 3 (HCVG3) was the most prevalent genotype, 71.4% (n = 100/140) and with the highest treatment response of 90% (n = 90/100). The overall treatment response of all the HCV genotypes was 82% (n = 115/140). The distribution of IL28B rs12979860CC genotype in treatment responder and non-responder groups was 40.8% (n = 47/115) and 16% (n = 4/25) respectively. IL28B rs12979860CC genotype demonstrated a significant correlation (p = 0.019) with interferon-based therapy of HCV infection. However, there was no observed association of IL28B rs8099917 polymorphism with treatment response in CHC patients (p = 0.264). In conclusion, HCV genotypes and IL28B rs12979860 are predictive markers for the efficiency of interferon plus ribavirin combinational therapy of HCV infection. We recommend the inclusion of testing for these markers in the clinical criteria for decision making for HCV therapy in Pakistani population.

Evaluation of the frequency of the IL-28 polymorphism (rs8099917) in patients with chronic hepatitis C using Zip nucleic acid probes, Kerman, Southeast of Iran

Polymorphisms in the region of the interleukin IL-28 gene on chromosome 19 have been related with clearance of hepatitis C virus (HCV), a major human pathogen responsible for chronic hepatitis, cirrhosis and hepatocellular carcinoma. About 3% of the world's population is infected with HCV. The long-term response to therapy is influenced by many host and viral factors, and recent evidence has indicated that some host genetic polymorphisms related to IL-28 are the most powerful predictors of virological response in patients with HCV. This study assessed frequency of the IL-28 polymorphism (rs8099917) in 50 patients (39 men and 11 women ) with chronic hepatitis C using ZNA probe real time PCR new method . All patients were tested for genotype of HCV and the HCV viral load. In parallel, the levels of SGOT, SGPT and ALK enzymes were assessed. Treatment using Peg-interferon alpha with ribavirin was conducted for patients and subsequently samples were collected to detect any change in viral load or liver enzyme rates. The overall frequency of the TT allele is 74%, TG allele 20% and GG allele 6% and the percent of patients who had T allele was 84%. Clear reduction in viral load and liver enzymes was reported in patients with the T allele. Especially for genotype 1 which is relatively resistant to treatment, these alleles may have a role in this decline. In conclusion, we showed that IL-28 polymorphism rs8099917 strongly predicts virological response in HCV infection and that real-time PCR with Zip nucleic acid probes is a sensitive, specific and rapid detection method for detection of SNPs which will be essential for monitoring patients undergoing antiviral therapy.