Approved Research

Systematic differences in colour vision genetics: investigating phenotypic correlations to sequence differences in OPN1LW, OPN1MW, and OPN1SW

Lay summary

The visual sense is one of the primary mechanisms of a human's interaction with their surroundings. Colour  vision  specifically  provides  rich  information  about  the  identities  of  objects  and  semantic content of a scene. Colour vision arises from the activation of the three cone photoreceptor types in the  retina:  the  short-[S],  medium-[M],  and  long-[L]  wavelength  sensitive  cones.  Each  contains  a photopigment determining its spectral sensitivity, the probability it will respond to light of a particular wavelength. The standard observer model offers a mean-based account of the cone spectral sensitivity functions and  how  these  feed  post-receptoral  pathways;  and  is  widely  used  in  the  lighting  and  colour reproduction industries to inform ergonomic design. In order to achieve inclusive design, it is crucial that the standard model is representative of diverse populations. Yet the current model is based solely on data from Caucasian observers, making it susceptible to systematic bias with respect to ethnicity. Evidence suggests that there are indeed differences in colour-vision mechanisms across ethnicity so bias in the standard model will translate to a diminished experience or performance impairment from colour reproduction technologies among non-Caucasian observers. One of the key sources of variability lies in the genetics. The photopigments are encoded by the OPN1LW, OPN1MW, and OPN1SW genes, and sequence differences in these genes result in individual variation in the cone spectral sensitivity functions which underpin colour vision. This project aims to quantify ethnicity, and other phenotypic, differences in the sequences of the OPN1LW, OPN1MW, and OPN1SW genes, and related colour vision genetic mechanisms. The project will last for three years, and will focus on uncovering the demographic correlates of variability in colour vision genetics. The overarching goal of this project is to feed into future development of a more inclusive standard model of colour vision which incorporates the full breadth of individual variability observed in a manner that prevents systematic bias, ultimately leading to inclusive, ergonomic design of lighting and displays.