Welcome to the forum.
This excerpt should help explain the Genotypes and the subtypes:
Genotypes
"Molecular differences between genotypes are relatively large, and they have a difference of at least 30% at the nucleotide level. The major HCV genotype worldwide is genotype 1, which accounts for 40-80% of all isolates. Genotype 1 also may be associated with more severe liver disease and a higher risk of HCC. Genotypes 1a and 1b are prevalent in the United States, whereas in other countries, genotype 1a is less frequent. HCV genotype 1, particularly 1b, does not respond to therapy as well as genotypes 2 and 3. Genotype details are as follows:
Genotype 1a occurs in 50-60% of patients in the United States; this type is difficult to eradicate using current medications
Genotype 1b occurs in 15-20% of patients in the United States; subtype 1b is also difficult to eradicate using current medications; this type is most prevalent in Europe, Turkey, and Japan
Genotype 1c occurs in less than 1% of patients in the United States
Genotypes 2a, 2b, and 2c occur in 10-15% of patients in the United States; these subtypes are widely distributed and are most responsive to medication
Genotypes 3a and 3b occur in 4-6% of patients in the United States; these subtypes are most prevalent in India, Pakistan, Thailand, Australia, and Scotland
Genotype 4 occurs in less than 5% of patients in the United States; it is most prevalent in the Middle East and Africa
Genotype 5 occurs in less than 5% of patients in the United States; it is most prevalent in South Africa
Genotype 6 occurs in less than 5% of patients in the United States; it is most prevalent in Southeast Asia, particularly Hong Kong and Macao "
http://emedicine.medscape.com/article/177792-overview#a0104
http://emedicine.medscape.com/article/177792-overview#aw2aab6b2b3
Just to add to the great info . pooh has given(as always ) Geno type 1a was shown in trial data to be somewhat toughter to treat succesfully than geno type 1bith triple therapy
With Inci the SVR rates were 79% for 1b vs. 71 % for 1a
And with Vic: 66-70% for 1b vs. 59 -63 % for 1a
The above reflects results for treatment naive patients and irrespective of other facors involved....
I will copy the data article later so you are not talking my word for it busy at the moment tho.. :)
Will