Abstract

Relative proportions of long-wavelength-sensitive (L) to middle-wavelength-sensitive (M) cones were estimated by use of the flicker-photometric electroretinogram (ERG). It has been demonstrated that a major source of error in estimates of cone proportions from spectral luminosity functions is the known variation in the λmax of the photopigments [Vision Res. 38, 1961 (1998)]. To correct for these errors, estimates of cone proportions were derived by use of individualized L-cone spectral sensitivity curves deduced from photopigment gene sequences from each subject. For some individuals this correction made a large difference in the estimated cone proportions compared with the value obtained when a fixed standard L cone was assumed. The largest discrepancy occurred in a man estimated to have 62% L cones (L:M ratio 1.6:1) when a standard L pigment was assumed but a value of 80% L cones (L:M ratio 4:1) when his individualized L-cone spectrum was used. From repeated measurements made with the ERG, it was determined that individual estimates of the relative L-to-M cone contributions, expressed as %L cones, are usually reliable within ∼2%. The average L:M ratio for 15 male subjects was estimated at 2:1 (67% L cones). Previously, a large range of individual variability was reported for L:M ratios obtained from photometry. An unresolved issue concerns how much of the range might be attributed to error. Here efforts have been taken to markedly reduce measurement error. Nonetheless, a large range of individual differences persists. Estimated L:M ratios for individuals ranged from 0.6:1 to 12:1 (40% L to 92% L).

© 2000 Optical Society of America

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  29. D. G. Stavenga, R. P. Smits, B. J. Hoenders, “Simple exponential functions describing the absorbance bands of visual pigment spectra,” Vision Res. 33, 1011–1017 (1993).
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    [PubMed]
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    [CrossRef]
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    [CrossRef]
  33. T. W. Kraft, J. Neitz, M. Neitz, “Spectra of human L cones,” Vision Res. 38, 3663–3670 (1998).
    [CrossRef]
  34. M. Neitz, J. Neitz, G. H. Jacobs, “Spectral tuning of pigments underlying red–green color vision,” Science 252, 971–974 (1991).
    [CrossRef] [PubMed]
  35. S. A. Sjoberg, M. Neitz, S. D. Balding, J. Neitz, “L-cone pigment genes expressed in normal colour vision,” Vision Res. 38, 3213–3219 (1998).
    [CrossRef]
  36. J. Winderickx, L. Battisti, Y. Hibibya, A. G. Motulsky, S. S. Deeb, “Haplotype diversity in the human red and green opsin genes: evidence for frequent sequence exchange in exon 3,” Hum. Mol. Genet. 2, 1413–1421 (1993).
    [CrossRef] [PubMed]
  37. S. A. Burns, A. E. Elsner, “Color matching at high illuminances: photopigment optical density and pupil entry,” J. Opt. Soc. Am. A 10, 221–230 (1993).
    [CrossRef] [PubMed]
  38. V. C. Smith, J. Pokorny, S. J. Starr, “Variability of color mixture data. I. Interobserver variability in the unit coordinates,” Vision Res. 16, 1087–1094 (1976).
    [CrossRef]
  39. J. Neitz, M. Neitz, J. C. He, S. K. Shevell, “Trichromatic color vision with only two spectrally distinct photopigments,” Nature Neurosci. 2, 884–888 (1999).
    [CrossRef] [PubMed]
  40. T. T. Berendschot, J. van de Kraats, D. van Norren, “Foveal cone mosaic and visual pigment density in dichromats,” J. Physiol. (London) 492, 307–314 (1996).
  41. J. Neitz, G. H. Jacobs, “Polymorphism in normal human color vision and its mechanism,” Vision Res. 30, 620–636 (1990).
    [CrossRef]
  42. D. Brainard, A. Roorda, J. Calderone, M. Neitz, J. Neitz, G. Jacobs, D. Williams, “Functional consequences of the relative numbers of L and M cones,” J. Opt. Soc. Am. A 17, 607–614 (2000).
    [CrossRef]

2000

1999

A. Roorda, D. R. Williams, “The arrangement of three cone classes in the living human eye,” Nature (London) 397, 520–522 (1999).
[CrossRef]

M. Hebert, V. Lachapelle, P. Lachapelle, “Reproducibility of ERG responses obtained with the DTL electrode,” Vision Res. 39, 1069–1070 (1999).
[CrossRef]

J. Neitz, M. Neitz, J. C. He, S. K. Shevell, “Trichromatic color vision with only two spectrally distinct photopigments,” Nature Neurosci. 2, 884–888 (1999).
[CrossRef] [PubMed]

1998

L. T. Sharpe, A. Stockman, H. Jagle, H. Knau, G. Klausen, A. Reitner, J. Nathans, “Red, green, and red–green hybrid pigments in the human retina: correlations between deduced protein sequences and psychophysically measured spectral sensitivities,” J. Neurosci. 18, 10053–10069 (1998).
[PubMed]

T. W. Kraft, J. Neitz, M. Neitz, “Spectra of human L cones,” Vision Res. 38, 3663–3670 (1998).
[CrossRef]

S. A. Sjoberg, M. Neitz, S. D. Balding, J. Neitz, “L-cone pigment genes expressed in normal colour vision,” Vision Res. 38, 3213–3219 (1998).
[CrossRef]

M. L. Bieber, J. M. Kraft, J. S. Werner, “Effects of known variations in photopigments on L/M cone ratios estimated from luminous efficiency functions,” Vision Res. 38, 1961–1966 (1998).
[CrossRef] [PubMed]

S. A. Hagstrom, J. Neitz, M. Neitz, “Variations in cone populations for red–green color vision examined by analysis of mRNA,” NeuroReport 9, 1963–1967 (1998).
[CrossRef] [PubMed]

1997

1996

G. H. Jacobs, J. Neitz, K. Krogh, “Electroretinogram flicker photometry and its applications,” J. Opt. Soc. Am. A 13, 641–648 (1996).
[CrossRef]

T. T. Berendschot, J. van de Kraats, D. van Norren, “Foveal cone mosaic and visual pigment density in dichromats,” J. Physiol. (London) 492, 307–314 (1996).

1995

T. D. Lamb, “Photoreceptor spectral sensitivities: common shape in the long-wavelength region,” Vision Res. 35, 3083–3091 (1995).
[CrossRef] [PubMed]

M. Neitz, J. Neitz, A. Grishok, “Polymorphism in the number of genes encoding long-wavelength sensitive cone pigments among males with normal color vision,” Vision Res. 35, 2395–2407 (1995).
[CrossRef] [PubMed]

1994

A. B. Asenjo, J. Rim, D. D. Oprian, “Molecular determinants of human red/green color discrimination,” Neuron 12, 1131–1138 (1994).
[CrossRef] [PubMed]

1993

M. Gendron-Maguire, T. Gridley, “Identification of transgenic mice,” Methods Enzymol. 225, 794–799 (1993).
[CrossRef] [PubMed]

D. G. Stavenga, R. P. Smits, B. J. Hoenders, “Simple exponential functions describing the absorbance bands of visual pigment spectra,” Vision Res. 33, 1011–1017 (1993).
[CrossRef] [PubMed]

S. A. Burns, A. E. Elsner, “Color matching at high illuminances: photopigment optical density and pupil entry,” J. Opt. Soc. Am. A 10, 221–230 (1993).
[CrossRef] [PubMed]

J. Winderickx, L. Battisti, Y. Hibibya, A. G. Motulsky, S. S. Deeb, “Haplotype diversity in the human red and green opsin genes: evidence for frequent sequence exchange in exon 3,” Hum. Mol. Genet. 2, 1413–1421 (1993).
[CrossRef] [PubMed]

1992

J. L. Nerger, C. M. Cicerone, “The ratio of L cones to M cones in the human parafoveal retina,” Vision Res. 32, 879–888 (1992).
[CrossRef] [PubMed]

1991

M. Wesner, J. Pokorny, S. Shevell, V. Smith, “Foveal cone detection statistics in color-normals and dichromats,” Vision Res. 31, 1021–1037 (1991).
[CrossRef] [PubMed]

M. Neitz, J. Neitz, G. H. Jacobs, “Spectral tuning of pigments underlying red–green color vision,” Science 252, 971–974 (1991).
[CrossRef] [PubMed]

J. C. Partridge, W. J. DeGrip, “A new template for rhodopsin (vitamin A1 based) visual pigments,” Vision Res. 31, 619–630 (1991).
[CrossRef]

1990

J. Neitz, G. H. Jacobs, “Polymorphism in normal human color vision and its mechanism,” Vision Res. 30, 620–636 (1990).
[CrossRef]

1989

C. M. Cicerone, J. L. Nerger, “The relative numbers of long-wavelength-sensitive to middle-wavelength-sensitive cones in the human fovea centralis,” Vision Res. 29, 115–128 (1989).
[CrossRef] [PubMed]

R. L. P. Vimal, J. Pokorny, V. C. Smith, S. K. Shevell, “Foveal cone thresholds,” Vision Res. 29, 61–78 (1989).
[CrossRef] [PubMed]

1987

D. A. Baylor, B. J. Nunn, J. L. Schnapf, “Spectral sensitivity of cones of the monkey Macaca fascicularis,” J. Physiol. (London) 390, 145–160 (1987).

J. L. Schnapf, T. W. Kraft, D. A. Baylor, “Spectral sensitivity of human cone photoreceptors,” Nature (London) 325, 439–441 (1987).
[CrossRef]

1986

E. F. MacNichol, “A unifying presentation of photopigment spectra,” Vision Res. 26, 1543–1556 (1986).
[CrossRef] [PubMed]

1984

1981

S. M. Dawis, “Polynomial expressions of pigment nomograms,” Vision Res. 21, 1427–1430 (1981).
[CrossRef] [PubMed]

1977

T. Ebrey, B. Honig, “New wavelength dependent visual pigment nomogram,” Vision Res. 17, 147–151 (1977).
[CrossRef]

1976

V. C. Smith, J. Pokorny, S. J. Starr, “Variability of color mixture data. I. Interobserver variability in the unit coordinates,” Vision Res. 16, 1087–1094 (1976).
[CrossRef]

1964

W. A. H. Rushton, H. D. Baker, “Red/green sensitivity in normal vision,” Vision Res. 4, 75–85 (1964).
[CrossRef] [PubMed]

1953

H. J. A. Dartnall, “The interpretation of spectral sensitivity curves,” Br. Med. Bull. 9, 24–30 (1953).
[PubMed]

1947

H. L. de Vries, “The heredity of the relative numbers of red and green receptors in the human eye,” Genetica (The Hague) 24, 199–212 (1947).

Asenjo, A. B.

A. B. Asenjo, J. Rim, D. D. Oprian, “Molecular determinants of human red/green color discrimination,” Neuron 12, 1131–1138 (1994).
[CrossRef] [PubMed]

Baker, H. D.

W. A. H. Rushton, H. D. Baker, “Red/green sensitivity in normal vision,” Vision Res. 4, 75–85 (1964).
[CrossRef] [PubMed]

Balding, S. D.

S. A. Sjoberg, M. Neitz, S. D. Balding, J. Neitz, “L-cone pigment genes expressed in normal colour vision,” Vision Res. 38, 3213–3219 (1998).
[CrossRef]

Battisti, L.

J. Winderickx, L. Battisti, Y. Hibibya, A. G. Motulsky, S. S. Deeb, “Haplotype diversity in the human red and green opsin genes: evidence for frequent sequence exchange in exon 3,” Hum. Mol. Genet. 2, 1413–1421 (1993).
[CrossRef] [PubMed]

Baylor, D. A.

J. L. Schnapf, T. W. Kraft, D. A. Baylor, “Spectral sensitivity of human cone photoreceptors,” Nature (London) 325, 439–441 (1987).
[CrossRef]

D. A. Baylor, B. J. Nunn, J. L. Schnapf, “Spectral sensitivity of cones of the monkey Macaca fascicularis,” J. Physiol. (London) 390, 145–160 (1987).

Berendschot, T. T.

T. T. Berendschot, J. van de Kraats, D. van Norren, “Foveal cone mosaic and visual pigment density in dichromats,” J. Physiol. (London) 492, 307–314 (1996).

Bieber, M. L.

M. L. Bieber, J. M. Kraft, J. S. Werner, “Effects of known variations in photopigments on L/M cone ratios estimated from luminous efficiency functions,” Vision Res. 38, 1961–1966 (1998).
[CrossRef] [PubMed]

Brainard, D.

Burns, S. A.

Calderone, J.

Cicerone, C. M.

J. L. Nerger, C. M. Cicerone, “The ratio of L cones to M cones in the human parafoveal retina,” Vision Res. 32, 879–888 (1992).
[CrossRef] [PubMed]

C. M. Cicerone, J. L. Nerger, “The relative numbers of long-wavelength-sensitive to middle-wavelength-sensitive cones in the human fovea centralis,” Vision Res. 29, 115–128 (1989).
[CrossRef] [PubMed]

Dartnall, H. J. A.

H. J. A. Dartnall, “The interpretation of spectral sensitivity curves,” Br. Med. Bull. 9, 24–30 (1953).
[PubMed]

Dawis, S. M.

S. M. Dawis, “Polynomial expressions of pigment nomograms,” Vision Res. 21, 1427–1430 (1981).
[CrossRef] [PubMed]

de Vries, H. L.

H. L. de Vries, “The heredity of the relative numbers of red and green receptors in the human eye,” Genetica (The Hague) 24, 199–212 (1947).

Deeb, S. S.

J. Winderickx, L. Battisti, Y. Hibibya, A. G. Motulsky, S. S. Deeb, “Haplotype diversity in the human red and green opsin genes: evidence for frequent sequence exchange in exon 3,” Hum. Mol. Genet. 2, 1413–1421 (1993).
[CrossRef] [PubMed]

DeGrip, W. J.

J. C. Partridge, W. J. DeGrip, “A new template for rhodopsin (vitamin A1 based) visual pigments,” Vision Res. 31, 619–630 (1991).
[CrossRef]

Ebrey, T.

T. Ebrey, B. Honig, “New wavelength dependent visual pigment nomogram,” Vision Res. 17, 147–151 (1977).
[CrossRef]

Elsner, A. E.

Gendron-Maguire, M.

M. Gendron-Maguire, T. Gridley, “Identification of transgenic mice,” Methods Enzymol. 225, 794–799 (1993).
[CrossRef] [PubMed]

Gridley, T.

M. Gendron-Maguire, T. Gridley, “Identification of transgenic mice,” Methods Enzymol. 225, 794–799 (1993).
[CrossRef] [PubMed]

Grishok, A.

M. Neitz, J. Neitz, A. Grishok, “Polymorphism in the number of genes encoding long-wavelength sensitive cone pigments among males with normal color vision,” Vision Res. 35, 2395–2407 (1995).
[CrossRef] [PubMed]

Hagstrom, S. A.

S. A. Hagstrom, M. Neitz, J. Neitz, “Cone pigment gene expression in individual photoreceptors and the chromatic topography of the retina,” J. Opt. Soc. Am. A 17, 527–537 (2000).
[CrossRef]

S. A. Hagstrom, J. Neitz, M. Neitz, “Variations in cone populations for red–green color vision examined by analysis of mRNA,” NeuroReport 9, 1963–1967 (1998).
[CrossRef] [PubMed]

S. A. Hagstrom, J. Neitz, M. Neitz, “Ratio of M/L pigment gene expression decreases with retinal eccentricity,” in Colour Vision Deficiencies XIII, C. R. Cavonius, ed. (Kluwer Academic, Dordrecht, The Netherlands, 1997), pp. 59–66.

He, J. C.

J. Neitz, M. Neitz, J. C. He, S. K. Shevell, “Trichromatic color vision with only two spectrally distinct photopigments,” Nature Neurosci. 2, 884–888 (1999).
[CrossRef] [PubMed]

Hebert, M.

M. Hebert, V. Lachapelle, P. Lachapelle, “Reproducibility of ERG responses obtained with the DTL electrode,” Vision Res. 39, 1069–1070 (1999).
[CrossRef]

Hibibya, Y.

J. Winderickx, L. Battisti, Y. Hibibya, A. G. Motulsky, S. S. Deeb, “Haplotype diversity in the human red and green opsin genes: evidence for frequent sequence exchange in exon 3,” Hum. Mol. Genet. 2, 1413–1421 (1993).
[CrossRef] [PubMed]

Hoenders, B. J.

D. G. Stavenga, R. P. Smits, B. J. Hoenders, “Simple exponential functions describing the absorbance bands of visual pigment spectra,” Vision Res. 33, 1011–1017 (1993).
[CrossRef] [PubMed]

Honig, B.

T. Ebrey, B. Honig, “New wavelength dependent visual pigment nomogram,” Vision Res. 17, 147–151 (1977).
[CrossRef]

Jacobs, G.

Jacobs, G. H.

G. H. Jacobs, J. Neitz, K. Krogh, “Electroretinogram flicker photometry and its applications,” J. Opt. Soc. Am. A 13, 641–648 (1996).
[CrossRef]

M. Neitz, J. Neitz, G. H. Jacobs, “Spectral tuning of pigments underlying red–green color vision,” Science 252, 971–974 (1991).
[CrossRef] [PubMed]

J. Neitz, G. H. Jacobs, “Polymorphism in normal human color vision and its mechanism,” Vision Res. 30, 620–636 (1990).
[CrossRef]

J. Neitz, G. H. Jacobs, “Electroretinogram measurements of cone spectral sensitivity in dichromatic monkeys,” J. Opt. Soc. Am. A 1, 1175–1180 (1984).
[CrossRef] [PubMed]

G. H. Jacobs, J. Neitz, “Electrophysiological estimates of individual variation in the L/M cone ratio,” in Color Vision Deficiencies XI, B. Drum, ed. (Kluwer Academic, Dordrecht, The Netherlands, 1993), pp. 107–112.

Jagle, H.

L. T. Sharpe, A. Stockman, H. Jagle, H. Knau, G. Klausen, A. Reitner, J. Nathans, “Red, green, and red–green hybrid pigments in the human retina: correlations between deduced protein sequences and psychophysically measured spectral sensitivities,” J. Neurosci. 18, 10053–10069 (1998).
[PubMed]

Klausen, G.

L. T. Sharpe, A. Stockman, H. Jagle, H. Knau, G. Klausen, A. Reitner, J. Nathans, “Red, green, and red–green hybrid pigments in the human retina: correlations between deduced protein sequences and psychophysically measured spectral sensitivities,” J. Neurosci. 18, 10053–10069 (1998).
[PubMed]

Knau, H.

L. T. Sharpe, A. Stockman, H. Jagle, H. Knau, G. Klausen, A. Reitner, J. Nathans, “Red, green, and red–green hybrid pigments in the human retina: correlations between deduced protein sequences and psychophysically measured spectral sensitivities,” J. Neurosci. 18, 10053–10069 (1998).
[PubMed]

Kraft, J. M.

M. L. Bieber, J. M. Kraft, J. S. Werner, “Effects of known variations in photopigments on L/M cone ratios estimated from luminous efficiency functions,” Vision Res. 38, 1961–1966 (1998).
[CrossRef] [PubMed]

Kraft, T. W.

T. W. Kraft, J. Neitz, M. Neitz, “Spectra of human L cones,” Vision Res. 38, 3663–3670 (1998).
[CrossRef]

J. L. Schnapf, T. W. Kraft, D. A. Baylor, “Spectral sensitivity of human cone photoreceptors,” Nature (London) 325, 439–441 (1987).
[CrossRef]

Krogh, K.

Lachapelle, P.

M. Hebert, V. Lachapelle, P. Lachapelle, “Reproducibility of ERG responses obtained with the DTL electrode,” Vision Res. 39, 1069–1070 (1999).
[CrossRef]

Lachapelle, V.

M. Hebert, V. Lachapelle, P. Lachapelle, “Reproducibility of ERG responses obtained with the DTL electrode,” Vision Res. 39, 1069–1070 (1999).
[CrossRef]

Lamb, T. D.

T. D. Lamb, “Photoreceptor spectral sensitivities: common shape in the long-wavelength region,” Vision Res. 35, 3083–3091 (1995).
[CrossRef] [PubMed]

MacNichol, E. F.

E. F. MacNichol, “A unifying presentation of photopigment spectra,” Vision Res. 26, 1543–1556 (1986).
[CrossRef] [PubMed]

Mansfield, R. J. W.

R. J. W. Mansfield, “Primate photopigments and cone mechanisms,” in The Visual System, A. Fein, J. S. Levine, eds. (Liss, New York, 1985), pp. 89–106.

Motulsky, A. G.

J. Winderickx, L. Battisti, Y. Hibibya, A. G. Motulsky, S. S. Deeb, “Haplotype diversity in the human red and green opsin genes: evidence for frequent sequence exchange in exon 3,” Hum. Mol. Genet. 2, 1413–1421 (1993).
[CrossRef] [PubMed]

Nathans, J.

L. T. Sharpe, A. Stockman, H. Jagle, H. Knau, G. Klausen, A. Reitner, J. Nathans, “Red, green, and red–green hybrid pigments in the human retina: correlations between deduced protein sequences and psychophysically measured spectral sensitivities,” J. Neurosci. 18, 10053–10069 (1998).
[PubMed]

Neitz, J.

S. A. Hagstrom, M. Neitz, J. Neitz, “Cone pigment gene expression in individual photoreceptors and the chromatic topography of the retina,” J. Opt. Soc. Am. A 17, 527–537 (2000).
[CrossRef]

D. Brainard, A. Roorda, J. Calderone, M. Neitz, J. Neitz, G. Jacobs, D. Williams, “Functional consequences of the relative numbers of L and M cones,” J. Opt. Soc. Am. A 17, 607–614 (2000).
[CrossRef]

J. Neitz, M. Neitz, J. C. He, S. K. Shevell, “Trichromatic color vision with only two spectrally distinct photopigments,” Nature Neurosci. 2, 884–888 (1999).
[CrossRef] [PubMed]

S. A. Hagstrom, J. Neitz, M. Neitz, “Variations in cone populations for red–green color vision examined by analysis of mRNA,” NeuroReport 9, 1963–1967 (1998).
[CrossRef] [PubMed]

T. W. Kraft, J. Neitz, M. Neitz, “Spectra of human L cones,” Vision Res. 38, 3663–3670 (1998).
[CrossRef]

S. A. Sjoberg, M. Neitz, S. D. Balding, J. Neitz, “L-cone pigment genes expressed in normal colour vision,” Vision Res. 38, 3213–3219 (1998).
[CrossRef]

G. H. Jacobs, J. Neitz, K. Krogh, “Electroretinogram flicker photometry and its applications,” J. Opt. Soc. Am. A 13, 641–648 (1996).
[CrossRef]

M. Neitz, J. Neitz, A. Grishok, “Polymorphism in the number of genes encoding long-wavelength sensitive cone pigments among males with normal color vision,” Vision Res. 35, 2395–2407 (1995).
[CrossRef] [PubMed]

M. Neitz, J. Neitz, G. H. Jacobs, “Spectral tuning of pigments underlying red–green color vision,” Science 252, 971–974 (1991).
[CrossRef] [PubMed]

J. Neitz, G. H. Jacobs, “Polymorphism in normal human color vision and its mechanism,” Vision Res. 30, 620–636 (1990).
[CrossRef]

J. Neitz, G. H. Jacobs, “Electroretinogram measurements of cone spectral sensitivity in dichromatic monkeys,” J. Opt. Soc. Am. A 1, 1175–1180 (1984).
[CrossRef] [PubMed]

M. Neitz, J. Neitz, “Molecular genetics and the biological basis of color vision,” in Color Vision—Perspectives from Different Disciplines, W. Backhaus, R. Kleigl, J. S. Werner, eds. (de Gruyter, Berlin, 1998), pp. 101–119.

G. H. Jacobs, J. Neitz, “Electrophysiological estimates of individual variation in the L/M cone ratio,” in Color Vision Deficiencies XI, B. Drum, ed. (Kluwer Academic, Dordrecht, The Netherlands, 1993), pp. 107–112.

S. A. Hagstrom, J. Neitz, M. Neitz, “Ratio of M/L pigment gene expression decreases with retinal eccentricity,” in Colour Vision Deficiencies XIII, C. R. Cavonius, ed. (Kluwer Academic, Dordrecht, The Netherlands, 1997), pp. 59–66.

Neitz, M.

D. Brainard, A. Roorda, J. Calderone, M. Neitz, J. Neitz, G. Jacobs, D. Williams, “Functional consequences of the relative numbers of L and M cones,” J. Opt. Soc. Am. A 17, 607–614 (2000).
[CrossRef]

S. A. Hagstrom, M. Neitz, J. Neitz, “Cone pigment gene expression in individual photoreceptors and the chromatic topography of the retina,” J. Opt. Soc. Am. A 17, 527–537 (2000).
[CrossRef]

J. Neitz, M. Neitz, J. C. He, S. K. Shevell, “Trichromatic color vision with only two spectrally distinct photopigments,” Nature Neurosci. 2, 884–888 (1999).
[CrossRef] [PubMed]

S. A. Hagstrom, J. Neitz, M. Neitz, “Variations in cone populations for red–green color vision examined by analysis of mRNA,” NeuroReport 9, 1963–1967 (1998).
[CrossRef] [PubMed]

S. A. Sjoberg, M. Neitz, S. D. Balding, J. Neitz, “L-cone pigment genes expressed in normal colour vision,” Vision Res. 38, 3213–3219 (1998).
[CrossRef]

T. W. Kraft, J. Neitz, M. Neitz, “Spectra of human L cones,” Vision Res. 38, 3663–3670 (1998).
[CrossRef]

M. Neitz, J. Neitz, A. Grishok, “Polymorphism in the number of genes encoding long-wavelength sensitive cone pigments among males with normal color vision,” Vision Res. 35, 2395–2407 (1995).
[CrossRef] [PubMed]

M. Neitz, J. Neitz, G. H. Jacobs, “Spectral tuning of pigments underlying red–green color vision,” Science 252, 971–974 (1991).
[CrossRef] [PubMed]

M. Neitz, J. Neitz, “Molecular genetics and the biological basis of color vision,” in Color Vision—Perspectives from Different Disciplines, W. Backhaus, R. Kleigl, J. S. Werner, eds. (de Gruyter, Berlin, 1998), pp. 101–119.

S. A. Hagstrom, J. Neitz, M. Neitz, “Ratio of M/L pigment gene expression decreases with retinal eccentricity,” in Colour Vision Deficiencies XIII, C. R. Cavonius, ed. (Kluwer Academic, Dordrecht, The Netherlands, 1997), pp. 59–66.

Nerger, J. L.

J. L. Nerger, C. M. Cicerone, “The ratio of L cones to M cones in the human parafoveal retina,” Vision Res. 32, 879–888 (1992).
[CrossRef] [PubMed]

C. M. Cicerone, J. L. Nerger, “The relative numbers of long-wavelength-sensitive to middle-wavelength-sensitive cones in the human fovea centralis,” Vision Res. 29, 115–128 (1989).
[CrossRef] [PubMed]

Nunn, B. J.

D. A. Baylor, B. J. Nunn, J. L. Schnapf, “Spectral sensitivity of cones of the monkey Macaca fascicularis,” J. Physiol. (London) 390, 145–160 (1987).

Oprian, D. D.

A. B. Asenjo, J. Rim, D. D. Oprian, “Molecular determinants of human red/green color discrimination,” Neuron 12, 1131–1138 (1994).
[CrossRef] [PubMed]

Partridge, J. C.

J. C. Partridge, W. J. DeGrip, “A new template for rhodopsin (vitamin A1 based) visual pigments,” Vision Res. 31, 619–630 (1991).
[CrossRef]

Pokorny, J.

J. Xu, J. Pokorny, V. C. Smith, “Optical density of the human lens,” J. Opt. Soc. Am. A 14, 953–960 (1997).
[CrossRef]

M. Wesner, J. Pokorny, S. Shevell, V. Smith, “Foveal cone detection statistics in color-normals and dichromats,” Vision Res. 31, 1021–1037 (1991).
[CrossRef] [PubMed]

R. L. P. Vimal, J. Pokorny, V. C. Smith, S. K. Shevell, “Foveal cone thresholds,” Vision Res. 29, 61–78 (1989).
[CrossRef] [PubMed]

V. C. Smith, J. Pokorny, S. J. Starr, “Variability of color mixture data. I. Interobserver variability in the unit coordinates,” Vision Res. 16, 1087–1094 (1976).
[CrossRef]

J. Pokorny, V. C. Smith, M. F. Wesner. “Variability in cone populations and implications,” in From Pigments to Perception, A. Valberg, B. B. Lee, eds. (Plenum, New York, 1991), pp. 23–33.

Reitner, A.

L. T. Sharpe, A. Stockman, H. Jagle, H. Knau, G. Klausen, A. Reitner, J. Nathans, “Red, green, and red–green hybrid pigments in the human retina: correlations between deduced protein sequences and psychophysically measured spectral sensitivities,” J. Neurosci. 18, 10053–10069 (1998).
[PubMed]

Rim, J.

A. B. Asenjo, J. Rim, D. D. Oprian, “Molecular determinants of human red/green color discrimination,” Neuron 12, 1131–1138 (1994).
[CrossRef] [PubMed]

Roorda, A.

Rushton, W. A. H.

W. A. H. Rushton, H. D. Baker, “Red/green sensitivity in normal vision,” Vision Res. 4, 75–85 (1964).
[CrossRef] [PubMed]

Schnapf, J. L.

D. A. Baylor, B. J. Nunn, J. L. Schnapf, “Spectral sensitivity of cones of the monkey Macaca fascicularis,” J. Physiol. (London) 390, 145–160 (1987).

J. L. Schnapf, T. W. Kraft, D. A. Baylor, “Spectral sensitivity of human cone photoreceptors,” Nature (London) 325, 439–441 (1987).
[CrossRef]

Sharpe, L. T.

L. T. Sharpe, A. Stockman, H. Jagle, H. Knau, G. Klausen, A. Reitner, J. Nathans, “Red, green, and red–green hybrid pigments in the human retina: correlations between deduced protein sequences and psychophysically measured spectral sensitivities,” J. Neurosci. 18, 10053–10069 (1998).
[PubMed]

Shevell, S.

M. Wesner, J. Pokorny, S. Shevell, V. Smith, “Foveal cone detection statistics in color-normals and dichromats,” Vision Res. 31, 1021–1037 (1991).
[CrossRef] [PubMed]

Shevell, S. K.

J. Neitz, M. Neitz, J. C. He, S. K. Shevell, “Trichromatic color vision with only two spectrally distinct photopigments,” Nature Neurosci. 2, 884–888 (1999).
[CrossRef] [PubMed]

R. L. P. Vimal, J. Pokorny, V. C. Smith, S. K. Shevell, “Foveal cone thresholds,” Vision Res. 29, 61–78 (1989).
[CrossRef] [PubMed]

Sjoberg, S. A.

S. A. Sjoberg, M. Neitz, S. D. Balding, J. Neitz, “L-cone pigment genes expressed in normal colour vision,” Vision Res. 38, 3213–3219 (1998).
[CrossRef]

Smith, V.

M. Wesner, J. Pokorny, S. Shevell, V. Smith, “Foveal cone detection statistics in color-normals and dichromats,” Vision Res. 31, 1021–1037 (1991).
[CrossRef] [PubMed]

Smith, V. C.

J. Xu, J. Pokorny, V. C. Smith, “Optical density of the human lens,” J. Opt. Soc. Am. A 14, 953–960 (1997).
[CrossRef]

R. L. P. Vimal, J. Pokorny, V. C. Smith, S. K. Shevell, “Foveal cone thresholds,” Vision Res. 29, 61–78 (1989).
[CrossRef] [PubMed]

V. C. Smith, J. Pokorny, S. J. Starr, “Variability of color mixture data. I. Interobserver variability in the unit coordinates,” Vision Res. 16, 1087–1094 (1976).
[CrossRef]

J. Pokorny, V. C. Smith, M. F. Wesner. “Variability in cone populations and implications,” in From Pigments to Perception, A. Valberg, B. B. Lee, eds. (Plenum, New York, 1991), pp. 23–33.

Smits, R. P.

D. G. Stavenga, R. P. Smits, B. J. Hoenders, “Simple exponential functions describing the absorbance bands of visual pigment spectra,” Vision Res. 33, 1011–1017 (1993).
[CrossRef] [PubMed]

Starr, S. J.

V. C. Smith, J. Pokorny, S. J. Starr, “Variability of color mixture data. I. Interobserver variability in the unit coordinates,” Vision Res. 16, 1087–1094 (1976).
[CrossRef]

Stavenga, D. G.

D. G. Stavenga, R. P. Smits, B. J. Hoenders, “Simple exponential functions describing the absorbance bands of visual pigment spectra,” Vision Res. 33, 1011–1017 (1993).
[CrossRef] [PubMed]

Stockman, A.

L. T. Sharpe, A. Stockman, H. Jagle, H. Knau, G. Klausen, A. Reitner, J. Nathans, “Red, green, and red–green hybrid pigments in the human retina: correlations between deduced protein sequences and psychophysically measured spectral sensitivities,” J. Neurosci. 18, 10053–10069 (1998).
[PubMed]

van de Kraats, J.

T. T. Berendschot, J. van de Kraats, D. van Norren, “Foveal cone mosaic and visual pigment density in dichromats,” J. Physiol. (London) 492, 307–314 (1996).

van Norren, D.

T. T. Berendschot, J. van de Kraats, D. van Norren, “Foveal cone mosaic and visual pigment density in dichromats,” J. Physiol. (London) 492, 307–314 (1996).

Vimal, R. L. P.

R. L. P. Vimal, J. Pokorny, V. C. Smith, S. K. Shevell, “Foveal cone thresholds,” Vision Res. 29, 61–78 (1989).
[CrossRef] [PubMed]

Werner, J. S.

M. L. Bieber, J. M. Kraft, J. S. Werner, “Effects of known variations in photopigments on L/M cone ratios estimated from luminous efficiency functions,” Vision Res. 38, 1961–1966 (1998).
[CrossRef] [PubMed]

Wesner, M.

M. Wesner, J. Pokorny, S. Shevell, V. Smith, “Foveal cone detection statistics in color-normals and dichromats,” Vision Res. 31, 1021–1037 (1991).
[CrossRef] [PubMed]

Wesner, M. F.

J. Pokorny, V. C. Smith, M. F. Wesner. “Variability in cone populations and implications,” in From Pigments to Perception, A. Valberg, B. B. Lee, eds. (Plenum, New York, 1991), pp. 23–33.

Williams, D.

Williams, D. R.

A. Roorda, D. R. Williams, “The arrangement of three cone classes in the living human eye,” Nature (London) 397, 520–522 (1999).
[CrossRef]

Winderickx, J.

J. Winderickx, L. Battisti, Y. Hibibya, A. G. Motulsky, S. S. Deeb, “Haplotype diversity in the human red and green opsin genes: evidence for frequent sequence exchange in exon 3,” Hum. Mol. Genet. 2, 1413–1421 (1993).
[CrossRef] [PubMed]

Xu, J.

Br. Med. Bull.

H. J. A. Dartnall, “The interpretation of spectral sensitivity curves,” Br. Med. Bull. 9, 24–30 (1953).
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Genetica (The Hague)

H. L. de Vries, “The heredity of the relative numbers of red and green receptors in the human eye,” Genetica (The Hague) 24, 199–212 (1947).

Hum. Mol. Genet.

J. Winderickx, L. Battisti, Y. Hibibya, A. G. Motulsky, S. S. Deeb, “Haplotype diversity in the human red and green opsin genes: evidence for frequent sequence exchange in exon 3,” Hum. Mol. Genet. 2, 1413–1421 (1993).
[CrossRef] [PubMed]

J. Neurosci.

L. T. Sharpe, A. Stockman, H. Jagle, H. Knau, G. Klausen, A. Reitner, J. Nathans, “Red, green, and red–green hybrid pigments in the human retina: correlations between deduced protein sequences and psychophysically measured spectral sensitivities,” J. Neurosci. 18, 10053–10069 (1998).
[PubMed]

J. Opt. Soc. Am. A

J. Physiol. (London)

D. A. Baylor, B. J. Nunn, J. L. Schnapf, “Spectral sensitivity of cones of the monkey Macaca fascicularis,” J. Physiol. (London) 390, 145–160 (1987).

T. T. Berendschot, J. van de Kraats, D. van Norren, “Foveal cone mosaic and visual pigment density in dichromats,” J. Physiol. (London) 492, 307–314 (1996).

Methods Enzymol.

M. Gendron-Maguire, T. Gridley, “Identification of transgenic mice,” Methods Enzymol. 225, 794–799 (1993).
[CrossRef] [PubMed]

Nature (London)

A. Roorda, D. R. Williams, “The arrangement of three cone classes in the living human eye,” Nature (London) 397, 520–522 (1999).
[CrossRef]

J. L. Schnapf, T. W. Kraft, D. A. Baylor, “Spectral sensitivity of human cone photoreceptors,” Nature (London) 325, 439–441 (1987).
[CrossRef]

Nature Neurosci.

J. Neitz, M. Neitz, J. C. He, S. K. Shevell, “Trichromatic color vision with only two spectrally distinct photopigments,” Nature Neurosci. 2, 884–888 (1999).
[CrossRef] [PubMed]

Neuron

A. B. Asenjo, J. Rim, D. D. Oprian, “Molecular determinants of human red/green color discrimination,” Neuron 12, 1131–1138 (1994).
[CrossRef] [PubMed]

NeuroReport

S. A. Hagstrom, J. Neitz, M. Neitz, “Variations in cone populations for red–green color vision examined by analysis of mRNA,” NeuroReport 9, 1963–1967 (1998).
[CrossRef] [PubMed]

Science

M. Neitz, J. Neitz, G. H. Jacobs, “Spectral tuning of pigments underlying red–green color vision,” Science 252, 971–974 (1991).
[CrossRef] [PubMed]

Vision Res.

S. A. Sjoberg, M. Neitz, S. D. Balding, J. Neitz, “L-cone pigment genes expressed in normal colour vision,” Vision Res. 38, 3213–3219 (1998).
[CrossRef]

T. W. Kraft, J. Neitz, M. Neitz, “Spectra of human L cones,” Vision Res. 38, 3663–3670 (1998).
[CrossRef]

J. Neitz, G. H. Jacobs, “Polymorphism in normal human color vision and its mechanism,” Vision Res. 30, 620–636 (1990).
[CrossRef]

V. C. Smith, J. Pokorny, S. J. Starr, “Variability of color mixture data. I. Interobserver variability in the unit coordinates,” Vision Res. 16, 1087–1094 (1976).
[CrossRef]

T. D. Lamb, “Photoreceptor spectral sensitivities: common shape in the long-wavelength region,” Vision Res. 35, 3083–3091 (1995).
[CrossRef] [PubMed]

J. C. Partridge, W. J. DeGrip, “A new template for rhodopsin (vitamin A1 based) visual pigments,” Vision Res. 31, 619–630 (1991).
[CrossRef]

T. Ebrey, B. Honig, “New wavelength dependent visual pigment nomogram,” Vision Res. 17, 147–151 (1977).
[CrossRef]

S. M. Dawis, “Polynomial expressions of pigment nomograms,” Vision Res. 21, 1427–1430 (1981).
[CrossRef] [PubMed]

D. G. Stavenga, R. P. Smits, B. J. Hoenders, “Simple exponential functions describing the absorbance bands of visual pigment spectra,” Vision Res. 33, 1011–1017 (1993).
[CrossRef] [PubMed]

E. F. MacNichol, “A unifying presentation of photopigment spectra,” Vision Res. 26, 1543–1556 (1986).
[CrossRef] [PubMed]

M. L. Bieber, J. M. Kraft, J. S. Werner, “Effects of known variations in photopigments on L/M cone ratios estimated from luminous efficiency functions,” Vision Res. 38, 1961–1966 (1998).
[CrossRef] [PubMed]

M. Hebert, V. Lachapelle, P. Lachapelle, “Reproducibility of ERG responses obtained with the DTL electrode,” Vision Res. 39, 1069–1070 (1999).
[CrossRef]

M. Neitz, J. Neitz, A. Grishok, “Polymorphism in the number of genes encoding long-wavelength sensitive cone pigments among males with normal color vision,” Vision Res. 35, 2395–2407 (1995).
[CrossRef] [PubMed]

R. L. P. Vimal, J. Pokorny, V. C. Smith, S. K. Shevell, “Foveal cone thresholds,” Vision Res. 29, 61–78 (1989).
[CrossRef] [PubMed]

W. A. H. Rushton, H. D. Baker, “Red/green sensitivity in normal vision,” Vision Res. 4, 75–85 (1964).
[CrossRef] [PubMed]

M. Wesner, J. Pokorny, S. Shevell, V. Smith, “Foveal cone detection statistics in color-normals and dichromats,” Vision Res. 31, 1021–1037 (1991).
[CrossRef] [PubMed]

C. M. Cicerone, J. L. Nerger, “The relative numbers of long-wavelength-sensitive to middle-wavelength-sensitive cones in the human fovea centralis,” Vision Res. 29, 115–128 (1989).
[CrossRef] [PubMed]

J. L. Nerger, C. M. Cicerone, “The ratio of L cones to M cones in the human parafoveal retina,” Vision Res. 32, 879–888 (1992).
[CrossRef] [PubMed]

Other

S. A. Hagstrom, J. Neitz, M. Neitz, “Ratio of M/L pigment gene expression decreases with retinal eccentricity,” in Colour Vision Deficiencies XIII, C. R. Cavonius, ed. (Kluwer Academic, Dordrecht, The Netherlands, 1997), pp. 59–66.

M. Neitz, J. Neitz, “Molecular genetics and the biological basis of color vision,” in Color Vision—Perspectives from Different Disciplines, W. Backhaus, R. Kleigl, J. S. Werner, eds. (de Gruyter, Berlin, 1998), pp. 101–119.

G. H. Jacobs, J. Neitz, “Electrophysiological estimates of individual variation in the L/M cone ratio,” in Color Vision Deficiencies XI, B. Drum, ed. (Kluwer Academic, Dordrecht, The Netherlands, 1993), pp. 107–112.

J. Pokorny, V. C. Smith, M. F. Wesner. “Variability in cone populations and implications,” in From Pigments to Perception, A. Valberg, B. B. Lee, eds. (Plenum, New York, 1991), pp. 23–33.

R. J. W. Mansfield, “Primate photopigments and cone mechanisms,” in The Visual System, A. Fein, J. S. Levine, eds. (Liss, New York, 1985), pp. 89–106.

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Figures (7)

Fig. 1
Fig. 1

Monochromatic test lights were obtained with a Varispec liquid-crystal electronically tunable filter incorporated into a compact three-channel Maxwellian-view optical system. The wavelength of the test beam was computer controlled with the tunable filter and could be varied in subnanometer increments over the range 400–700 nm. An achromatic reference light was derived from a second beam. The test and the reference lights were presented alternately with an interposed off period through the use of high-speed shutters. A third beam can be used to provide accessory adaptation, but it was blocked in the experiments reported here.

Fig. 2
Fig. 2

Wavelength-adjustable expression for use in curve fitting spectral sensitivity data. The expression was designed to correspond to the extinction spectrum of bovine rhodopsin31 over the top of the curve. Rhodopsin data are indicated by pluses. The spectral limbs were made to fit to spectral sensitivities of L cones measured electrophysiologically (triangles, measurements of Kraft et al.33; squares, measurements of Schnapf et al.32). The expression met three additional design criteria: (1) that the curve be described by a single continuous function, (2) that the function be well behaved at all wavelengths from 180 nm below the peak to infinity, and (3) that the long-wavelength side have a linear asymptote with a slope of 30.4 when the data are plotted on a normalized frequency scale.

Fig. 3
Fig. 3

A, Photopigment template expression used here compared with previously reported expressions. The template curves of both Baylor et al.24 and Sharpe et al.30 deviate from linearity in the very long-wavelength region. Lamb’s template expression25 was not designed to represent the pigment shape in the short-wavelength region. Near its peak, our curve was designed to match the bovine rhodopsin spectrum to extremely close tolerances. In the region near the peak of the curve, mismatches between our template and the earlier expressions closely mirror differences between those templates and the rhodopsin extinction spectrum. The accuracy of our curve near its peak depends on the assumptions that the rhodopsin curve is accurate31 and that rhodopsin and the M and L pigment spectra are identical when they are translated on a log wave-number scale. B, Difference between our template curve and each of the others. The differences are plotted on a greatly expanded scale. Even though most of the differences are of the order of 0.01–0.1 log unit over the range of visible wavelengths, they are large enough to have a significant effect on estimated cone ratio derived from linear combinations of these curves.

Fig. 4
Fig. 4

Reliability of ERG spectral sensitivity functions. Spectral sensitivity values are shown as filled circles; standard deviations from the trials are shown as open circles. The solid curves represent the averages. A, Five independent measurements of spectral sensitivity on a single deuteranope (subjects 015) over a 2-month test period. Each spectral sensitivity function was fitted to a template curve from our expression (with OD fixed at 0.35), and λmax was recorded. B, Spectral sensitivity functions for four single gene deuteranopes with identical L pigment sequences. The test for each subject was run once, and his spectral sensitivity function was fitted to the template curve. The resultant λmax values were recorded. C, D, Each panel plots five repeated measures of spectral sensitivity for one color-normal subject. %L was calculated as the weighted sum of the subject’s individualized L and the standard M fundamental. (L, λmax=559.09,OD=0.35 and λmax=559.11,OD=0.35, respectively; M, λmax=530,OD=0.22.)

Fig. 5
Fig. 5

Distribution of L-cone relative to M-cone contributions to ERG spectral sensitivity determined for 15 men with normal color vision. The relative L:M contributions are represented in terms of %L in linear combination with M required to best fit each subject’s flicker-photometric ERG spectral sensitivity function. An individualized L pigment spectral sensitivity curve was derived from each subject’s L pigment gene sequence.

Fig. 6
Fig. 6

L-cone pigment λmax and estimated %L-cone contributions compared with Nagel anomaloscope Rayleigh match settings for 15 men with normal color vision. A, λmax of the L cone determined from L pigment gene sequences versus anomaloscope setting. B, %L-cone contribution calculated with a fixed standard L-cone fundamental versus anomaloscope setting. C, Same as B, except that the %L contribution was corrected by use of individualized L-cone fundamentals for each subject. D, Same as C, except that %L values were calculated by use of only the spectral sensitivity points at wavelengths that were ⩾550 nm.

Fig. 7
Fig. 7

Individual variations in %L observed in the spectral sensitivity function. The L-cone template curve that corresponds to that pigment is shown by the solid curve in A and in B. The two subjects (who represent the extremes observed in these experiments) have dramatically different spectral sensitivity functions (filled circles). The differences in spectral sensitivity presumably represent large differences in L:M cone contributions to the ERG signal.

Tables (1)

Tables Icon

Table 1 L Pigment Sequences and ERG-Derived %L for 15 Normal Male Subjects

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