Defects in CYP4F22 are the cause of ichthyosis lamellar type 3 (LI3). LI is a non-bullous ichthyosis, a skin disorder characterized by abnormal cornification of the epidermis. It is one the most severe forms of ichthyoses apparent at birth and persisting throughout life. LI patients are born encased in a tight, shiny, translucent covering called collodion membrane. Over the first weeks of life, the collodion membrane is gradually replaced by generalized large, dark brown, plate-like scales with minimal to no erythroderma. Tautness of facial skin commonly results in ectropion, eclabium and scarring alopecia of the scalp. Common complications are severe heat intolerance and recurrent ear infections. Belongs to the cytochrome P450 family. Note: This description may include information from UniProtKB.