Counterphase modulation flicker photometry: phenotypic and genotypic associations.
The OSCAR test, a clinical device that uses counterphase flicker photometry, is believed to be sensitive to the relative numbers of long-wavelength and middle-wavelength cones in the retina, as well as to individual variations in the spectral positions of the photopigments. As part of a population study of individual variations in perception, we obtained OSCAR settings from 1058 participants. We report the distribution characteristics for this cohort. A randomly selected subset of participants was tested twice at an interval of at least one week: the test-retest reliability (Spearman's rho) was 0.80. In a whole-genome association analysis we found a provisional association with a single nucleotide polymorphism (rs16844995). This marker is close to the gene RXRG, which encodes a nuclear receptor, retinoid X receptor γ. This nuclear receptor is already known to have a role in the differentiation of cones during the development of the eye, and we suggest that polymorphisms in or close to RXRG influence the relative probability with which long-wave and middle-wave opsin genes are expressed in human cones.
A J
AJ
Lawrance-Owen
J M
JM
Bosten
R E
RE
Hogg
G
G
Bargary
P T
PT
Goodbourn
J D
JD
Mollon
D000293:Adolescent; D000328:Adult; D016477:Artifacts; D005260:Female; D023281:Genomics; D005838:Genotype; D006801:Humans; D008297:Male; D010641:Phenotype; D010783:Photometry / Q000379:methods*; D020641:Polymorphism, Single Nucleotide; D015203:Reproducibility of Results; D017949:Retinal Cone Photoreceptor Cells / Q000166:cytology* / Q000378:metabolism; D047491:Retinoid X Receptor gamma / Q000235:genetics; D055815:Young Adult
D047491:Retinoid X Receptor gamma