What are the genetic changes related to familial pityriasis rubra pilaris ?
In most cases of pityriasis rubra pilaris, the cause of the condition is unknown. However, mutations in the CARD14 gene have been found to cause the familial form of the disorder in a few affected families. The CARD14 gene provides instructions for making a protein that turns on (activates) a group of interacting proteins known as nuclear factor-kappa-B (NF-B). NF-B regulates the activity of multiple genes, including genes that control the body's immune responses and inflammatory reactions. It also protects cells from certain signals that would otherwise cause them to self-destruct (undergo apoptosis).  The CARD14 protein is found in many of the body's tissues, but it is particularly abundant in the skin. NF-B signaling appears to play an important role in regulating inflammation in the skin. Mutations in the CARD14 gene lead to overactivation of NF-B signaling, which triggers an abnormal inflammatory response. Researchers are working to determine how these changes lead to the specific features of familial pityriasis rubra pilaris.