Visual Neuroscience



GENETICS

A novel mutation in the short-wavelength-sensitive cone pigment gene associated with a tritan color vision defect


KAREN L.  GUNTHER  a1 , JAY  NEITZ  a1 and MAUREEN  NEITZ  a1 c1
a1 Department of Ophthalmology and Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin

Article author query
gunther kl   [Google Scholar] 
neitz j   [Google Scholar] 
neitz m   [Google Scholar] 
 

Abstract

Inherited tritan color vision deficiency is caused by defects in the function of the short-wavelength-sensitive (S) cones. This heterozygous group of disorders has an autosomal dominant pattern of inheritance. Amino acid variations of the S cone opsin are rare and all that have been identified thus far are associated with inherited tritan color vision defects. Here we report the identification of a 30-year-old male who made errors on standard color vision tests consistent with the presence of a mild tritan color vision deficiency. We tested the hypothesis that his color vision impairment was due to a mutation in the S cone photopigment gene. He was found to be heterozygous for a mutation that caused the amino acid proline to be substituted in place of a highly conserved leucine at amino acid position 56 in the S cone opsin. This mutation was absent in 564 S cone photopigment genes from 282 subjects who did not make tritan errors. Thus, we conclude that this mutation disrupts the normal function of S cones.

(Received September 15 2005)
(Accepted January 13 2006)


Key Words: Inherited tritanopia; S-cone opsin mutation; Photopigment; Color vision.

Correspondence:
c1 Address correspondence and reprint requests to: Maureen Neitz, Department of Ophthalmology, Medical College of Wisconsin, 925 N. 87th Street, Milwaukee, WI 53226-4812, USA. E-mail: mneitz@mcw.edu