Originally Posted by lin1949
What does Genotyping mean. I know the doctor will explain this, but I don't know when I can get in yet.
There have been several identified "species" of the hepatitis C virus.
Think of genotyping (the test, anyway) as a rainbow. Genotyping is the "color" given to the point on a spectrum where your blood sample shows the species.
Some genotypes are very specific and obvious on a result sample. Some are not so simple and may either blend together ot be somewhat hard to pin down. It is still not an exact science in terms of the testing. That is why a few people will be told that their genotype is "mixed." It is not clear on the blot where the positive result actually is.
In the USA, the most common genotype is 1. Very often this can be divided into 1a and 1b.
Genotypes 2 and 3 are the next most common genotype. They can be identified sometimes in subtypes as well (2a, for example)
Other genotypes are less clear or are given based on the best guess of the lab doc.
Genotypes 4 and 6 are rare in the USA.
The utility of genotyping currently has to do with length of treatment decisions. A geno 1 should be treated for at least a year. Genotypes 2 and 3; for six months. One genotype is no more serious than another, they simply respond to the interferon differently.
I hope this is clear enough to be helpful.