Figure 2: Gel electrophoresis of polymerase chain reaction product. Numbers 1, 3, 4, and 5 are HTLV1-positive samples which showed 256 bp and 149 bp fragments of HTLV1 TAX and human TATA-binding protein (internal control of PCR) genes, respectively. Number 2 is a 100 bp DNA size marker. Number 6 is a negative control of PCR.