A rapid method for determination of the relative copy number of HTLV-I proviral genome in HTLV-I carriers and adult T-cell leukemia patients by polymerase chain reaction.

Ten adult T-cell leukemia (ATL) patients and 11 asymptomatic human T-cell leukemia virus type I (HTLV-I) carriers were examined by polymerase chain reaction (PCR) assay with a reduced sensitivity to evaluate its utility in detecting the relative copy number of the HTLV-I genome in clinical samples. Differences in the intensities of the PCR products were observed between the acute type ATL patients and ATL patients in remission or carriers. Intense bands were found in all acute type ATL patients (6/6, 100%), while specific bands were seen in only 2 carriers (2/11, 18.2%). The bands found in one of the two patients in remission were weak. One patient, who had acute type ATL, had achieved a remission but later relapsed. Using this technique, we examined the differences in the intensities of the bands of the PCR products in a patient with acute type ATL who had achieved remission but later relapsed. Thus, this technique may be of clinical importance in diagnosing acute ATL and assessing the effect of therapy.