A DEFINED REGION OF LOSS OF HETEROZYGOSITY AT 11Q23 IN CUTANEOUS MALIGNANT-MELANOMA

Karyotypic and molecular data indicate that genetic alterations of the long arm of chromosome 11 (11q) may be involved in malignant melanoma . To test this we analyzed 5 polymorphic microsatellite repeats on 11q using a PCR-based assay for loss of heterozygosity in normal and tumo r tissues from 24 individuals with cutaneous malignant melanoma of var ious stages. Our findings indicate that a tumor suppressor gene that p lays a role in malignant melanoma is located on the long arm of chromo some 11, likely within a 51 cM region at 11q23. Its loss appears to be a late event in tumor progression and may serve as an indicator for a less favorable clinical outcome.