Such a mechanism has been identified in Ambras syndrome, a rare disorder caused by a translocation with a break point in the Trps1 promoter, leading to the aberrant pattern of Trps1 expression.47 Unlike TRPS patients that are characterized by sparse slow-growing hair, the most prominent feature of Ambras syndrome is extensive growth of hair over the entire body (hypertrichosis). Here, TRPS1 is linked to hypertrichosis.