Interleukin-28B polymorphism in persons with chronic hepatitis C in Croatia

Polimorfizam jednog nukleotida (engl. single nucleotide polymorphism, SNP) rs12979860 u blizini promotora gena za interleukin-28B (IL-28B) tj. genotipizacija IL-28B povezana je s prirodnim tijekom infekcije virusom hepatitisa C kao i s odgovorom na antivirusno i imunomodulacijsko liječenje kombinacijom pegiliranog interferona alfa i ribavirina (tzv. dvojna terapija). U eri direktno djelujućih antivirusnih lijekova genotip IL-28B više nije značajan prediktor ishoda liječenja no i dalje je važan parametar koji određuje prirodni tijek povijesti HCV infekcije. U zemljama koje nemaju univerzalni pristup novim terapijskim opcijama genotipizacija IL-28B i dalje se primjenjuje u pred-terapijskoj obradi bolesnika koji se liječe dvojnom terapijom. Cilj ovog rada bio je analizirati rezultate genotipizacije IL-28B (udio homozigota za T i C alel te heterozigota) u 595 bolesnika s kroničnim hepatitisom C koji su bili uključeni u kliničku skrb Zavoda za virusni hepatitis Klinike za infektivne bolesti "Dr. Fran Mihaljević" u Zagrebu od siječnja 2013. do prosinca 2015. g. SNP rs12979860 detektiran je metodom lančane reakcije polimerazom u stvarnom vremenu. Analiza SNP-a rs12979860 u genu za IL-28B pokazala je da su 335 od 595 (56,3%) ispitanika bili CT heterozigoti, 173 od 595 ispitanika (29,1%) C homozigoti i 87 od 595 ispitanika (14,6%) T homozigoti. Distribucija C i T alela u SNP-u rs12979860 gena za IL-28B sukladni su literaturnim podatcima analize prevalencije ovih alela u osoba bijele rase europskog porijekla.Single nucleotide polymorphism (SNP) rs12979860 in the promotor region of the gene coding for interleukin-28B (IL-28B) is associated with the natural history of hepatitis C virus (HCV) infection and response to antiviral and immunomodulatory therapy with combination of pegylated interferon alpha and ribavirin (dual therapy). Despite the fact that the predictive role IL-28B genotyping is decreasing in the era of highly successful direct acting antiviral (DAA)-based treatment, it remains to be useful as a tool for predicting a natural course of HCV infection. In resource-limited settings with restricted access to new treatment options IL-28B polymorphism typing is still a part of pre-treatment workup before admission of dual therapy. The aim of this study was to analyse the results of IL-28B genotyping (percentages of C and T homozygotes and heterozygotes) for 595 Caucasian patients with chronic hepatitis C receiving clinical care at the Department of Viral Hepatitis of the University Hospital for Infectious Diseases, Zagreb and Croatian Reference Center for Viral Hepatitis since January 2013 till December 2015. Detection of single nucleotide polymorphism (SNP) rs12979860 was determined by using a real-time PCR test. Analysis of rs12979860 SNP in the IL-28B gene showed that 335 of 595 (56.3%) patients were CT heterozygotes, followed by C homozygotes (173 of 595 patients, 29.1%) whereas T homozygotes were the least frequent (87 of 595 patients, 14.6%). The patterns of IL-28 polymorphism in Croatian patients with chronic hepatitis C is in accordance with other results for Caucasians