LOCALIZATION OF A NOVEL TUMOR-SUPPRESSOR LOCUS ON HUMAN-CHROMOSOME 3QIMPORTANT IN OSTEOSARCOMA TUMORIGENESIS

Mitotic recombination or nondysjunction are common mechanisms for tumo r-specific loss of constitutional heterozygosity (LOH) and tumor suppr essor allelic inactivation and can be useful in localizing new putativ e tumor suppressor genes. In osteosarcoma, the highest frequencies of LOH have been reported for chromosomes 3q, 13q, 17p, and 18q. The high incidence of LOM on chromosomes 3q suggests the presence of a novel t umor suppressor gene, To localize this putative tumor suppressor gene, we have used polymorphic markers on chromosome 3q to define the minim al region in which mitotic recombination or deletion results in LOH, w hich should contain the tumor suppressor gene, This putative tumor sup pressor has been localized to a region between 3q26.2-3q25.3 of less t han 1 cM between the polymorphic loci D3S1212 and D3S1246.