Just like there are different types of hepatitis viruses, there are also a few different types of the hepatitis C virus itself. Though they all cause hepatitis C, each type of the virus has a slightly different arrangement of its genetic material, in this case called "RNA". The specific arrangement of the RNA is called the "genotype".
The main genotypes of the hepatitis C virus are known as genotype 1, 2, 3, 4, 5, and 6. Of these different genotypes, genotype 1 is the type most commonly found in the United States. Genotypes 2 and 3 are less common. Only ten to twenty percent of infected people in this country have either of these genotypes.