Validation of interleukin 28B genotyping assay for clinical use

Objectives: The favorable CC genotype at rs12979860 upstream of the interleukin (IL)-28B gene is correlated with a greater post-treatment sustained virologic response rate in chronic hepatitis C infected patients. We report on our validation of a clinical genotyping assay for rs12979860 polymorphisms in the IL28B locus.

Design and methods: The rs12979860 genotype was determined using a TaqMan® Real-Time PCR allelic discrimination assay with primers and probes specific for the C and T alleles on the Applied Biosystems 7500 Fast Real-Time PCR System.

Results: The rs12979860 genotype determined by our assay was concordant with the genotypes obtained from a reference laboratory. The allelic frequency was similar to that reported in the HapMap project (rs12979860 C=0.65, T=0.35) and did not deviate from Hardy-Weinberg equilibrium.

Conclusion: Clinical availability of this assay in conjunction with other factors will allow the prediction of the individual patient's response to therapy.