Genetic variation in the interleukin-28B gene is associated with spontaneous clearance and progression of hepatitis C virus in Moroccan patients

Genetic variation in the IL28B gene has been strongly associated
with treatment outcomes, spontaneous clearance and progression of
the hepatitis C virus infection (HCV). The aim of the present study
was to investigate the role of polymorphisms at this locus with
progression and outcome of HCV infection in a Moroccan population.
We analyzed a cohort of 438 individuals among them 232 patients
with persistent HCV infection, of whom 115 patients had mild
chronic hepatitis and 117 had advanced liver disease (cirrhosis and
hepatocellular carcinoma), 68 individuals who had naturally cleared
HCV and 138 healthy subjects. The IL28B SNPs rs12979860 and
rs8099917 were genotyped using a TaqMan 5' allelic discrimination
assay. The protective rs12979860-C and rs8099917-T alleles were
more common in subjects with spontaneous clearance (77.9% vs 55.2%;
p = 0.00001 and 95.6% vs 83.2%; p = 0.0025, respectively).
Individuals with clearance were 4.69 (95% CI, 1.99-11.07) times
more likely to have the C/C genotype for rs12979860 polymorphism (p
= 0.0017) and 3.55 (95% CI, 0.19-66.89) times more likely to have
the T/T genotype at rs8099917. Patients with advanced liver disease
carried the rs12979860-T/T genotype more frequently than patients
with mild chronic hepatitis C (OR = 1.89; 95% CI, 0.99-3.61; p =
0.0532) and this risk was even more pronounced when we compared
them with healthy controls (OR = 4.27; 95% CI, 2.08-8.76; p =
0.0005). The rs8099917-G allele was also associated with advanced
liver disease (OR = 2.34; 95% CI, 1.40-3.93; p = 0.0100). In the
Moroccan population, polymorphisms near the IL28B gene play a role
both in spontaneous clearance and progression of HCV infection.