Expression of MDR genes in Scott and normal control EBV-transformed B lymphocytes. RNA was extracted from three EBV-transformed B-lymphoblast cell lines derived from a patient with Scott syndrome (S0, S1, S2) and three normal volunteers (C1, C2, W9), and RT-PCR performed with primers specific for MDR1, MDR3, and β₂-microglobulin (control gene), respectively. PCR products were separated by agarose gel electrophoresis and visualized by ethidium bromide staining. See Materials and Methods for details.