From HCV Advocate.org October Newsletter
Unlocking Interferon
—Alan Franciscus, Editor-in-Chief

Two separate news stories released in September are shedding some light on a
little known single nucleotide polymorphism (SNP) that is believed to affect
both patients who naturally clear HCV as well as those who will not respond to
pegylated interferon plus ribavirin therapy.

In the first news report from Johns Hopkins Medicine, researchers analyzed DNA
at the IL28B gene of 1008 patients—388 patients who were able to naturally clear
HCV after an acute infection and 620 patients who were not able to naturally
clear the virus. Of the 388 patients who were able to naturally resolve HCV
infection, 264 patients carried a C/C variation near the IL28B gene. When the
researchers looked at the gene variation by race the results were very
interesting: In Asians, 738 out of 824 samples carried the variation; in
Europeans 520 out of 761 carried the variation and in Africans only 148 out of
428 carried the variation. Although the news report didn't reference the
implications of the gene and HCV treatment response rates, it is interesting
that, when you look at current treatment response rates by race, the variation
somewhat mirrors the general response rates by race.

In another news story, Nature Genetics on-line reported on two studies that
looked at the effect of IL28B on predicting treatment response with pegylated
interferon alpha-a plus ribavirin. The first study, the Australian genome-wide
association study (GWAS), evaluated blood samples from 293 genotype 1 HCV
patients—131 who responded to pegylated interferon plus ribavirin treatment and
162 who did not. The authors found that a single nucleotide polymorphism (SNP)
on chromosome 19 between IL28A and IL28B was the only SNP that was significantly
associated with treatment non-response at the genome-wide level.

A separate study by the Japanese genome-wide association identified the same SNP
among 154 HCV genotype 1 Japanese patients—72 responders, 82 non-responders. To
replicate the results they conducted another study of 174 Japanese genotype 1
patients—122 responders and 52 non-responders and confirmed the earlier results.
The authors noted that in 85% of patients who did not respond to treatment, an
SNP at IL28B was detected.

The author speculated that a combination of different types of interferons such
as alpha and lambda may be more effective in treating hepatitis C than using
just a single type of interferon.

Best Wishes,
http://www.healthyhepper.com