DRM/GREMLIN (CKTSF1B1) maps to human chromosome 15 and is highly expressedin adult and fetal brain

We have mapped and characterized the human homolog of Drm/Gremlin (CKTFS1B1 ), a member of a family of BMP antagonists that have been linked to both de velopmental and transformation-related functions. By screening a human cDNA library, we isolated a 3.3-kb cDNA containing the 552-bp region encoding t he human DRM protein. CKTFS1B1 was localized on human chromosome 15q13 --> q15 by somatic cell hybrid analysis and, more precisely, using radiation hy brids, to a region of markers linked to SGNE1, secretory granule neuroendoc rine protein 1 and RYR3, the ryanodyne receptor 3. Northern blot analysis s howed the presence of a single DRM-specific mRNA expressed ill different hu man tissues, including brain, ovary, intestine and colon. In the brain, DRM expression is associated with the region localized around the internal cap sule in the large subcortical nuclei. DRM appears to be predominantly expre ssed in normal cells and tissues, including normal neurons, astrocytes and fibroblasts. Interestingly, we detected DRM expression in normal cells obta ined from several patients, but not in tumor cell lines established from th e same patients. The data suggest that down-regulation of DRM is associated with tumor progression, and support the hypothesis that human DRM may play an important role during both neuroembryological development and carcinoge nesis. Copyright(C)2000S.KargerAG,Basel.