REPETITIVE PLASMID SEQUENCES GENERATE DNA-FINGERPRINTING PATTERNS IN MAMMALS

Bacterial plasmids with stringently regulated copy numbers have direct ly repeated DNA sequences, termed iterons, in the vicinity of their re plication origins. These sequences bind a specific protein exerting a key role in the initiation of plasmid replication. Plasmids P1, pSC101 and RFS1010 have different iteron sequences and belong to three diffe rent incompatibility groups. Used as DNA probes each of these plasmids generates specific patterns in mammals similar to those obtained by t he DNA fingerprinting technique. The iteron-containing regions were id entified as the part of the plasmids responsible for those patterns by using polymerase chain reaction (PCR) amplified DNA segments that con tained the iteron regions as probes.