A novel gene called ING1 encoding a 33-kDa protein that is an inhibitor of cell growth and a candidate tumor suppressor has been recently isolated (Garkavtsev et al., 1996). Here we show, using indirect immunofluorescence, that the protein (p331NG1) is located in the nucleus, which is consistent with its proposed role as a growth regulator. In addition, we show that a genomic probe to human ING1 localizes to chromosome 13 at q33→q34 by fluorescence in situ hybridization. This candidate tumor suppressor gene is located near a chromosome region which has been reported to be a site for translocation and deletion in gastric cancers and head and neck squamous carcinomas.