Preliminary mapping of the deleted region of chromosome 9 in bladder cancer.

Inactivation of a suppressor gene by deletion of chromosome 9 is a candidate initiating event in bladder carcinogenesis. We have used 13 polymorphic markers spanning the length of chromosome 9 in order to map the region of deletion in human bladder carcinomas. In the majority of tumors loss of heterozygosity was found at all informative sites along the chromosome, indicating deletion of the entire chromosome. Nine tumors had selective deletions of chromosome 9. Mapping of the deleted region in these tumors suggests that the target gene is located between D9S22 at 9q22 and D9S18 at 9p12-13.