REMI-RFLP MAPPING IN THE DICTYOSTELIUM GENOME

A set of 147 Dictyostelium discaideum strains was constructed by rando m integration of a vector containing rare restriction sites. The strai ns were generated by transformation using restriction enzyme-mediated integration (REMI) which results in the integration of linear DNA frag ments into randomly distributed genomic restriction sites. Restriction fragment length polymorphism (RFLP) was generated in a single genomic site in each strain. These REMI-RFLP strains were used to confirm gen e linkages previously supported by two other physical mapping techniqu es: yeast artificial chromosome (YAC) contig construction, and megabas e-scale restriction mapping. New linkages were uncovered when two or m ore hybridization probes identified the same RFLP fragments. Probes fo r 100 genes have marked 53% of the RFLPs, representing greater than 22 Mb of the 40 Mb Dictyostelium genome. Alignment of these and other la rge fragments along each chromosome should lead to a complete physical map of the Dictyostelium genome.