We have previously identified and regionally localized 195 chromosome-22-specific DNA markers. We now report restriction fragment length polymorphisms detected by 9 phage markers mapped to 22q11-q12, two cosmid clones mapped to 22q12-q13 and one plasmid mapped to 22q13-qter. These markers may be useful tools for mapping disease genes such as the NF2 locus, on chromosome 22.