Objective: To analyze transfusion transmitted virus (TTV) genotype in hepatitis patients and healthy people.
Methods: DNA fragment of TTV was amplified by polymerase chain reaction with nested primers in eight patients with liver disease and three healthy persons. The nested PCR products were cloned and sequenced.
Results: A TTV DNA sequence of 222 bp (primer sequence excluded) was compared among the 11 subjects. The similarity between N22 and WH1, WH2, WH3, GZ1, GZ2, GZ3, SD2, SD3 was 97.0%, 97.0%, 98.0%, 98.0%, 95.0%, 95.0%, 94.6% and 95.5%, respectively. The similarity between TXO11 and GZ4, SD1, XJ1 was 98.0%, 98.0% and 95.0%, respectively.
Conclusion: According to Okamoto's method, the eleven TTV clones are classified into two subtypes: genotype 1a and 1b.