T-TRACK PCR FINGERPRINTING FOR THE RAPID DETECTION OF GENETIC-POLYMORPHISM

The diversity of DNA sequences can be analyzed by comparing randomly a mplified polymorphic DNA, or restriction fragment length polymorphism fragments of DNA. Such analyses are dependent on the selection of appr opriate restriction enzyme(s) and/or primers. We have investigated a s impler approach to providing sensitive and specific genotyping. Cyclic extension of target sequences with dideoxythymidine generates PCR pro ducts with variable lengths. We analyzed these variable PCR products b y scoring the number of variable bands and comparing the scores (numer ical profiles) to establish similarities. We found that the polymorphi c lengths of the PCR products were comparable among serologically defi ned strains. It suggests that this single PCR reaction followed by a o ne-step electrophoresis yields easily analyzable data that can be comp ared with data from other gels.