Palmoplantar keratoderma and perioral keratotic plaques with hypotrichosis in a child.

The periorificial involvement is the unique characteristic of OS that differentiates it from the other severe forms of PPK[2] including Clouston syndrome, pachyonychia congenital, Vohwinkel syndrome, Mal de Meleda syndrome, Papillon-Lefèvre syndrome, Haim-Munk syndrome, and tyrosinemia type II. This mutation occurred in an intron, and intron mutations generally do not cause clinical disease; however, a few intron mutations could lead to errors in mRNA editing and further affect protein synthesis. Exome sequencing reveals mutations in TRPV3 as a cause of Olmsted syndrome. [Extracted from the article]