Comparative integromics on the breast cancer-associated gene KIAA1632: clues to a cancer antigen domain.

Sequence analysis of protein-coding human genes in human breast and colorectal cancer recently identified the KIAA1632 gene as a potential contributor to neoplastic processes in breast cancer. In the present study, we characterized the KIAA1632 gene by computational methods: detailed investigation of the genomic structure, protein prediction, identification of orthologs in other species and phylogenetic analysis. The human KIAA1632 gene was located within human genome sequence AC090355 and consists of 44 exons. KIAA1632 is located on chromosome 18q12.3-q21.1. These findings were determined by aligning the potential full-length transcript NM_020964 to the genomic sequence. The existing predicted gene model could be refined based on these alignments (using additional EST data). Protein sequence was predicted from the full-length transcript and possible orthologs in other species were identified. Using rigorous phylogenetic methods we were able to draw conclusions about the evolutionary history of these proteins. Comparison of the protein sequences of KIAA1632 and its orthologs revealed a shared 'signature motif'. This 'signature motif' was found in three well-characterized cancer antigens, raising the hypothesis of a common 'signature motif' for a certain group of cancer antigens.