Construction of a 1.5-Mb bacterial artificial chromosome contig in Xp11.23, a region of high gene content

To generate sequence-ready templates for the gene-rich Xp11.23 region, we have constructed a 1.5-Mb bacterial artificial chromosome (BAC) contig spanning the interval between the DNA markers OATL1 and DXS255. The contig includes 28 BACs, ranging in size from 58 to 285 kb with an average size of 135 kb, which provide 2.5-Fold coverage of the region. The BAC contig was constructed based entirely on the content of 40 DNA markers from a previously established YAC contig and II new markers developed from BAG-end DNA sequences, 4 of which mere required to close gaps in the map. There was no evidence of rearrangement, instability, or chimerism in any of the BAG clones. The BAG cloning system appears to provide robust and total physical coverage of this gene-rich region with clones that are suitable for DNA sequencing. (C) 1998 Academic Press.