<unk>  is a rare disorder with an unknown prevalence. As of 2018, the International<unk>  Research Registry has identified approximately 774 individuals with the disease, but prevalence is estimated to be 5,000–10,000 worldwide. The disease affects both males and females.
Pachyonychia congenita
Platonychia
Lipoatrophia annularis
Linitis plastica
Hapalonychia
Steatopygia
Koilonychia
Trachonychia