Long-range restriction map of human chromosome 22q11-22q12 between the lambda immunoglobulin locus and the Ewing...

A long-range restriction map of the region between the immunoglobulin lambda locus and the Ewing sarcoma breakpoint has been constructed using the rare-cutting enzymes NotI, NruI, AscI, and BsiWI. The map spans approximately 11,000 kb and represents about one-fifth of the long arm of chromosome 22. Thirty-nine markers, including seven NotI junction clones as well as numerous genes and anonymous sequences, were mapped to the region with a somatic cell hybrid panel. These probes were then used to produce the map. The seven NotI junction clones each identified a possible CpG island. The breakpoints of the RAJ5 hybrid and the Ewing sarcoma t(11;22) were also localized in the resulting map. This physical map will be useful in studying chromosomal rearrangements in the region, as well as providing the details to examine the fidelity of the YAC and cosmid contigs currently under construction. Comparisons of this physical map to genetic and radiation hybrid maps are discussed.