Darier Disease (DD) or dyskeratosis follicularis is a rare autosomal dominant inherited disorder (prevalence: 1–3:100,000) defined by heterozygous mutations in the ATP2A2 gene encoding the sarcoendoplasmic reticulum Ca2+ ATPase isoform 2 (SERCA2)1. The gene discussed is ATP2A2; the disease is Darier disease.