FinDis - Finnish Disease Database

Choroideremia (CHM)


  • Chm, rab escort protein 1 (CHM)


Choroideremia (CHM) is an X-linked recessive eye disease causing degeneration of the choriocapillaris, retinal pigment epithelium, and photoreceptors, leading to severe visual impairment by adulthood. The CHM gene on chromosome Xq21.2 encodes the Rab escort protein-1 (REP1) subunit of a protein geranylgeranyltransferase type II, which has a very important role in membrane trafficking. Several animal models for CHH have been developed, but the specific pathogenetic mechanisms are still unclear. The first clinical manifestation in CHM is night blindness during early adulthood, followed by reduction of central vision and constriction of visual fields. The choroid and retina undergo complete atrophy. Heterozygous female carriers have no visual defect but often show striking funduscopic changes such as irregular pigmentation and atrophy around the optic disc. Funduscopy examination forms the basis of clinical diagnosis. Diagnosis can be confirmed by gene test.


UMLS Concept names

Selected publications

  • van den Hurk JA, van de Pol TJ, Molloy CM, Brunsmann F, Rüther K, Zrenner E, Pinckers AJ, Pawlowitzki IH, Bleeker-Wagemakers EM, Wieringa B, et al. Detection and characterization of point mutations in the choroideremia candidate gene by PCR-SSCP analysis and direct DNA sequencing. Am J Hum Genet. 1992 Jun;50(6):1195-202. PMID:1598901 (Pubmed)
  • Tolmachova T, Wavre-Shapton ST, Barnard AR, MacLaren RE, Futter CE, Seabra MC. Retinal pigment epithelium defects accelerate photoreceptor degeneration in cell type-specific knockout mouse models of choroideremia. Invest Ophthalmol Vis Sci. 2010 Oct;51(10):4913-20.. PMID:20445111 (Pubmed)