The Hox homeobox genes encode proteins that are transcriptional regulators with an established role in embryonic development. HoxC5 is a 222 amino acid protein that localizes to the nucleus and contains one homeobox DNA-binding domain. Existing as multiple alternatively spliced isoforms, HoxC5 functions as a sequence-specific DNA-binding transcription factor that is part of a regulatory mechanism that provides cells with positional identities during development. The gene encoding HoxC5 maps to a cluster of Hox proteins on chromosome 12 that are essential for morphogenesis. Encoding over 1,100 genes within 132 million bases, chromosome 12 makes up about 4.5% of the human genome. A number of skeletal deformities are linked to chromosome 12, including hypochondrogenesis, achondrogenesis and Kniest dysplasia.