Number and variations of the red and green visual pigment genes in Japanese men with normal color vision.
OBJECTIVE
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.
Hayashi
S
S
Department of Ophthalmology, Shiga University of Medical Science, Seta, Otsu, Japan.
Ueyama
H
H
Tanabe
S
S
Yamade
S
S
Kani
K
K
D003118:Color Perception / Q000235:genetics*; D003117:Color Vision Defects / Q000235:genetics; D004247:DNA / Q000032:analysis; D017931:DNA Primers / Q000737:chemistry; D005091:Exons; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D018807:Polymorphism, Single-Stranded Conformational; D017949:Retinal Cone Photoreceptor Cells / Q000378:metabolism; D012168:Retinal Pigments / Q000235:genetics* / Q000378:metabolism; D014960:X Chromosome / Q000235:genetics
D017931:DNA Primers; D012168:Retinal Pigments; D004247:DNA