A) RAPD patterns of Corynebacterium diphtheriae isolated from 1995 to 1997. Lane 1, 1740 (strain #), gravis, G1/4 RAPD type strain. Lane 2, B327, gravis, G1/4 (RAPD type), 1997 (year of isolation). Lane 3, B400, mitis, G1/4, 1995. Lane 4, 490, gravis, G1/4 ribotyping type strain. Lane 5, B375, gravis, G1/4, 1995. Lane 6, B294, mitis, G1/4, 1996. Lane 7, B325, gravis, G4v, 1997. Lane 8, 860, mitis, M1/M1v RAPD type strain. Lane 9, B389, mitis, M1/M1v, 1995. Lane 10, B324, mitis, M1/M1v, 1997. Lan