Molecular biology-based assays
that detect the HCV RNA genome: PCR
assays This assay is so sensitive that it can detect as few as 50 viral particles
per milliliter of blood. This method is also used to determine the hepatitis C virus subtype (genotype),
which is very important since different subtypes respond differently to therapy. Because the virus mutates
so freely, patients often have multiple, genetically different, copies of the hepatitis C virus known
as ‘quasispecies’. In other words, the hepatitis C infection exists as a diverse set of hepatitis C
RNAs within a given subtype. PCR is the standard method used
for determination of the quasispecies.
