Send us a Message

Submit Data |  Help |  Video Tutorials |  News |  Publications |  Download |  REST API |  Citing RGD |  Contact   


The Human Phenotype Ontology (HPO) is downloaded weekly from The file downloaded is considered the "last stable build" available for the ontology. For more about the HPO, view their website at

Term:Harlequin phenomenon
go back to main search page
Accession:HP:0025531 term browser browse the term
Definition:The Harlequin phenomenon consists of a sudden change in skin colour, resulting in two different body colours, one on each half of the body.
Comment:The Harlequin phenomenon (HF) is most common in the newborn and can be a generalized phenomenon or only involve a specific body area. The HF of the newborn is thought to be secondary to a relative hypothalamic control immaturity of the sympathetic peripheral vascular tonus, although it has also been described in other age groups, primarily located to the face and neck and mostly caused by a sympathetic disautonomy. While certainly peculiar, the HF is a benign event in the newborn.

show annotations for term's descendants           Sort by:

Term paths to the root
Path 1
Term Annotations click to browse term
  Human phenotype 0
    Phenotypic abnormality 0
      Abnormality of the integument 0
        Abnormality of the skin 0
          Abnormality of skin physiology 0
            Harlequin phenomenon 0
paths to the root