PFGE restriction patterns of MRSA pattern VII and MSSA pattern ΔVII isolates. Lane 1, MRSA pattern VII strain from patient 1; lane 2, MRSA pattern VII strain from patient 2; lane 3, MSSA pattern ΔVII strain from patient 1; lane 5, DNA ladder (n × 48.5-kb fragments); lane 6, MSSA pattern ΔVII strain from patient 2; lanes 4, 7, 8, 9, and 10, MSSA pattern ΔVII strains from other patients