CONSTRUCTION AND CHARACTERIZATION OF 3 REGION-SPECIFIC MICRODISSECTION LIBRARIES FOR HUMAN-CHROMOSOME-18

Three region-specific libraries for the entire human chromosome 18 wer e constructed using microdissection and MboI linker-adaptor microcloni ng techniques, The libraries included 18pter-p11.1 (designated 18P lib rary), 18q11.1-q12.3 (18Q1 library), and 18q21.1-qter (18Q2 library). Samples of the microclones from each library were analyzed in derail, The insert sizes ranged between 50-600 bp, with a mean of 180-220 bp f or the three libraries, The libraries contained approximately 40-60% m icroclones with unique sequence inserts. More than 30 unique sequence microclones from each library were analyzed by Southern blot hybridiza tion to demonstrate that they are human specific and were derived from chromosome 18, The human genomic HindIII fragments hybridized to each microclone were determined and microclones cross-hybridized to rodent species were identified. These region-specific libraries and the uniq ue sequence microclones from the libraries are useful reagents for (1) isolating highly polymorphic microsatellite markers for refined linka ge analysis, (2) identifying corresponding YAC, BAC or other clones wi th large inserts for contig assembly and high resolution physical mapp ing, (3) isolating cDNA clones from the dissected region, and (4) conv enient sequencing of the microclones to prepare high density markers a nd sequence-ragged sites (STSs). Such applications have been demonstra ted in a series of similarly constructed microdissection libraries fro m other regions of the human genome.