A BAC-based physical map of the major autosomes of Drosophila melanogaster

We constructed a bacterial artificial chromosome (BAC)-based physical map o f chromosomes 2 and 3 of Drosophila melanogaster, which constitute 81% of t he genome. Sequence tagged site (STS) content, restriction fingerprinting, and polytene chromosome in situ hybridization approaches were integrated to produce a map spanning the euchromatin. Three of five remaining gaps are i n repeat-rich regions near the centromeres. A tiling path of clones spannin g this map and STS maps of chromosomes X and 4 was sequenced to low coverag e; the maps and tiling path sequence were used to support and verify the wh ole-genome sequence assembly, and tiling path BACs were used as templates i n sequence finishing.