A 300 KILOBASE INTERVAL GENETIC-MAP OF RICE INCLUDING 883 EXPRESSED SEQUENCES

We have constructed a high resolution rice genetic map containing 1,38 3 DNA markers at an average interval of 300 kilobases (kb). The marker s, distributed along 1,575 cM on 12 linkage groups, comprise 883 cDNAs , 265 genomic DNAs, 147 randomly amplified polymorphic DNAs (RAPD) and 88 other DNAs. cDNAs were derived from rice root and callus, analysed by single-run sequencing and searched for similarities with known pro teins. Nearly 260 rice genes are newly identified and mapped, and geno mic DNA and cloned RAPD fragments were also sequenced to generate STSs . Our map is the first significant gene expression map in plants. It i s also the densest genetic map available in plants and the first to be backed up comprehensively by clone sequence data.