The NVRL has added IL28B genotyping to the repertoire of tests at the NVRL.
Recent genome wide association studies identified IL28B genetic polymorphisms as strong predictors of spontaneous clearance of Hepatitis C virus (HCV) and response to peglFNa and ribavirin combination therapy in HCV genotype 1 infected individuals. Subsequent studies showed that combination peglFNa and ribavirin therapy in these patients was 2- to 3-fold more likely to be successful if patients were carriers of the CC (rs12979860) genotype as compared with either CT or TT genotypes. IL28B genotype was the strongest predictor of sustained virological response, showing a higher odds ratio (OR = 5.2) than any of the other independently associated predictors of treatment response such as baseline viral RNA levels, fibrosis stage or ethnicity.
IL28B polymorphism genotyping should ideally be requested pre-treatment in conjunction with baseline HCV RNA loads and HCV genotype to provide a comprehensive assessment of the likelihood of treatment response. The NVRL report will document the presence of the CC genotype or the alternative CT or TT genotypes.
Please note that this test involves characterisation of a fragment of the human genome and therefore the ethical implications of this investigation should be considered by your institution before routine test requesting commences. Indeed, patient consent may be advisable.
If you would like more information regarding this service, please contact me or a member of the NVRL clinical team at 01 7161236/1240/1349.