Analysis of DUX gene expression in cervical tumors and cell lines by RT-PCR. Top row: Southern blot hybridization of PCR products with the DUX4-specific  P-labeled oligonucleotide. Middle and bottom rows, electrophoregrams after ethidium bromide staining. GAPDH, a control for RNA stability and concentration. RT, reverse transcriptase; Nc, normal cervix from non-cervical-cancer patients; T, tumor; N, tumor-adjacent normal tissue. Patient numbers are as in figure 3.