Finding homes for orphan cytochrome P450s: CYP4V2 and CYP4F22 in disease states

Mol Interv. 2011 Apr;11(2):124-32. doi: 10.1124/mi.11.2.10.


The cytochrome P450 (CYP) 4 family of enzymes contains several recently identified membersthat are referred to as “orphan P450s” because their endogenous substrates are unknown.Human CYP4V2 and CYP4F22 are two such orphan P450s that are strongly linked to ocular andskin disease, respectively. Genetic analyses have identified a wide spectrum of mutations in the CYP4V2gene from patients suffering from Bietti’s crystalline corneoretinal dystrophy, and mutations in theCYP4F22 gene have been linked to lamellar ichthyosis. The strong gene–disease associations provideunique opportunities for elucidating the substrate specificity of these orphan P450s and unraveling thebiochemical pathways that may be impacted in patients with CYP4V2 and CYP4F22 functional deficits.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Corneal Dystrophies, Hereditary / enzymology
  • Corneal Dystrophies, Hereditary / etiology
  • Corneal Dystrophies, Hereditary / genetics
  • Corneal Dystrophies, Hereditary / metabolism
  • Cytochrome P-450 Enzyme System / genetics
  • Cytochrome P-450 Enzyme System / metabolism*
  • Cytochrome P450 Family 4
  • Fatty Acids / metabolism
  • Humans
  • Ichthyosis, Lamellar / enzymology*
  • Ichthyosis, Lamellar / genetics
  • Ichthyosis, Lamellar / metabolism
  • Retinal Diseases / enzymology
  • Retinal Diseases / etiology
  • Retinal Diseases / genetics
  • Retinal Diseases / metabolism
  • Substrate Specificity


  • Fatty Acids
  • Cytochrome P-450 Enzyme System
  • CYP4F22 protein, human
  • CYP4V2 protein, human
  • Cytochrome P450 Family 4

Supplementary concepts

  • Bietti Crystalline Dystrophy