The introduction of chromosome 10p into human glioblastoma or prostate cancer cells has been demonstrated to suppress their malignant phenotype, suggesting the presence of glioma or prostate tumor suppressor genes on 10p. As a resource for the fine mapping of these genes, a series of human-rodent hybrid cell lines containing single transferable fragments (STFs) of 10p were constructed. Normal chromosome 10 tagged with a neomycin-resistance gene on its short arm was fragmented by gamma-irradiation of 5-10krad, transferred into mouse L cells or Chinese hamster ovary cells by microcell-mediated chromosome transfer (MMCT), and then selected against G418. Thirty-three independent rodent-human hybrids carrying various-sized STFs were obtained. Polymerase chain reaction (PCR)-based genotyping revealed that these STFs contained the whole, or portions, of a 43-cM region on 10p14-pter and could be defined by 19 sequence-tagged-site (STS) markers. Using this panel of hybrids as donors for further MMCT, genes on the refined fragments could be transferred into other cells. This hybrid panel would therefore be a useful resource for the fine mapping of the genes on 10p14-pter to segments of about 2.4 cM by functional complementation.