Number and variations of the red and green visual pigment genes in Japanese men with normal color vision

Jpn J Ophthalmol. Jan-Feb 2001;45(1):60-7. doi: 10.1016/s0021-5155(00)00298-7.

Abstract

Purpose: We analyzed the red/green visual pigment genes in color-normal Japanese men to understand the relationship between color anomalies and genetic defects.

Methods: DNA from 120 color-normal Japanese men was subjected to polymerase chain reaction (PCR)-amplification for exons 2-5 of the red/green visual pigment genes and the PCR products were sequenced. The red:green gene ratios were estimated from the sequencing electropherograms of exon 5 and also from MvaI-restriction fragment analysis of the same exon. The first gene and the downstream genes in the pigment gene array were separately analyzed by PCR, direct sequencing, and/or single-strand conformation polymorphisms.

Results: The red:green gene ratios estimated from the ratios of peak heights of nucleotides on the sequencing electropherograms coincided with those estimated from the MvaI-restriction fragment analysis. Among the subjects analyzed, they were 1:1 in 43% (n = 52), 1:2 in 41% (n = 49), 1:3 in 6% (n = 7), and 1:>3 in 9% (n = 11). The first gene in the pigment gene arrays was red in all subjects. Only 1 subject (N22) had a green-red hybrid gene. Exons 2 and 4 had 2 haplotypes each, but exon 3 was highly polymorphic. Exon 5 of the green genes had one polymorphism at codon 283 with a frequency of 32%.

Conclusions: The features of visual pigment genes in color-normal Japanese men were revealed. The data and establishing techniques may be useful for analyzing these genes in color-deficient subjects in the Japanese population.

MeSH terms

  • Color Perception / genetics*
  • Color Vision Defects / genetics
  • DNA / analysis
  • DNA Primers / chemistry
  • Exons
  • Humans
  • Male
  • Polymerase Chain Reaction
  • Polymorphism, Genetic
  • Polymorphism, Single-Stranded Conformational
  • Retinal Cone Photoreceptor Cells / metabolism
  • Retinal Pigments / genetics*
  • Retinal Pigments / metabolism
  • X Chromosome / genetics

Substances

  • DNA Primers
  • Retinal Pigments
  • DNA