PFGE profiles of 10 isolates of V. parahaemolyticus from patient group 16. Lanes 1 and 12 (molecular weight markers, lambda ladder; Bio-Rad Laboratories); lanes 2, 3, and 6, O3:K6, GS-PCR-positive isolates; lanes 4, 5, 7, 8, and 10, O4:K8, GS-PCR-negative isolates; lanes 9 and 11, O4:K8, GS-PCR-positive isolates.