Mutations in the cone photoreceptor G-protein alpha-subunit gene GNAT2 in patients with achromatopsia

Am J Hum Genet. 2002 Aug;71(2):422-5. doi: 10.1086/341835. Epub 2002 Jun 20.


Achromatopsia is an autosomal recessively inherited visual disorder that is present from birth and that features the absence of color discrimination. We here report the identification of five independent families with achromatopsia that segregate protein-truncation mutations in the GNAT2 gene, located on chromosome 1p13. GNAT2 encodes the cone photoreceptor-specific alpha-subunit of transducin, a G-protein of the phototransduction cascade, which couples to the visual pigment(s). Our results demonstrate that GNAT2 is the third gene implicated in achromatopsia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Color Vision Defects / etiology
  • Color Vision Defects / genetics*
  • Humans
  • Molecular Sequence Data
  • Mutation*
  • Pedigree
  • Retinal Cone Photoreceptor Cells / metabolism*
  • Transducin / genetics*


  • Transducin

Associated data

  • GENBANK/X15088
  • GENBANK/Z18859
  • OMIM/MIM139340
  • OMIM/MIM216900
  • OMIM/MIM262300