The genotype testing works like this:
First you do a PCR to amplify the quantity of viral RNA you have
Then you add probes that attach to GT1, GT2, GT3, GT4, GT5, GT6
Then you wash the probes out and see how much has stuck to the viral RNA
And get results like
So you'd call that GT1 (which we know is a bit like GT4) and just a bit like the others.
In reality it looks like this where you can see a pure 1a and pure 1b on the left, then a 1a/1b