C17orf28 (chromosome 17 open reading frame 28) is a 788 amino acid multi-pass membrane protein that is expressed in heart, skeletal muscle, colon, spleen, kidney, liver, small intestine and lung. C17orf28 may be involved in the development of cancers in a broad range of tissues. Existing as three alternatively spliced isoforms, C17orf28 is encoded by a gene mapping to human chromosome 17, which makes up over 2.5% of the human genome with about 81 million bases encoding over 1,200 genes. Two key tumor suppressor genes are associated with chromosome 17, namely, p53 and BRCA1.