HOXC13

HOXC13, or homeobox C13, is a human gene encoding a transcription factor that belongs to the HOX gene family. It is located within the HOXC cluster on chromosome 12. Like other HOX genes, HOXC13 encodes a protein containing a homeodomain that binds DNA and regulates transcription, contributing to embryonic development and patterning along the anterior-posterior axis. In humans and other mammals, HOXC13 expression is enriched in developing skin and hair follicles, with mRNA detected in keratinocytes during hair shaft formation; in adult skin, its expression is largely restricted to hair follicle compartments.

Functionally, HOXC13 participates in the regulation of genes involved in epidermal differentiation and hair shaft formation. It likely acts in a regulatory network with other HOX genes and transcriptional cofactors such as PBX and MEIS proteins, modulating downstream targets that shape hair morphology and keratinocyte maturation.

Regulation of HOXC13 involves developmental cues and chromatin context; its expression patterns are conserved across vertebrates, though precise regulatory elements vary between species.

Clinical relevance: genetic and expression studies have examined HOXC13 in relation to hair and skin phenotypes. Variants or misexpression of HOXC13 have been associated with hereditary hair disorders and ectodermal dysplasia-like phenotypes in some families and model systems, supporting a role in hair follicle biology. However, HOXC13’s contribution to human disease remains under investigation, with no widely used diagnostic implications.

See also: HOX gene cluster, PBX/MEIS cofactors, hair follicle biology.