Somatic cell hybrid deletion map of human chromosome 18.

The creation of a physical map of chromosome 18 will be useful for the eventual identification of specific chromosomal regions that are critical in the occurrence of Edwards syndrome, the 18q- syndrome, and the 18p- syndrome. To begin the investigation of these syndromes, a physical map has been constructed to order random DNA fragments to specific portions of chromosome 18. A set of somatic cell hybrids that retain deletions or translocations involving chromosome 18 has been isolated and characterized. Over 200 lambda phage from a chromosome 18-specific library have been localized to 11 distinct regions of chromosome 18 using the chromosomal breakpoints present in the somatic cell hybrids.