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Related Experiment Video

Updated: Jun 15, 2026

Electrophysiological Methods for Measuring Photopigment Levels in Drosophila Photoreceptors

Electrophysiological Methods for Measuring Photopigment Levels in Drosophila Photoreceptors

Published on: June 2, 2022

Variable retinal phenotypes caused by mutations in the X-linked photopigment gene array.

Liliana Mizrahi-Meissonnier¹, Saul Merin, Eyal Banin

¹Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel.

Investigative Ophthalmology & Visual Science

|March 12, 2010

Summary

Mutations in the long (L) and middle (M) wavelength-sensitive cone opsin genes cause various X-linked cone-dominated retinal diseases. Genetic analysis of the L-M opsin gene array is crucial for diagnosing these conditions.

Related Experiment Videos

Last Updated: Jun 15, 2026

Electrophysiological Methods for Measuring Photopigment Levels in Drosophila Photoreceptors

Electrophysiological Methods for Measuring Photopigment Levels in Drosophila Photoreceptors

Published on: June 2, 2022

Area of Science:

Ophthalmology
Genetics
Molecular Biology

Background:

Cone-dominated phenotypes represent a spectrum of inherited retinal diseases.
X-linked inheritance patterns are common in certain retinal disorders affecting cone function.

Purpose of the Study:

To investigate the role of long (L) and middle (M) wavelength-sensitive cone opsin genes in cone-dominated visual phenotypes.
To identify genetic mutations responsible for X-linked cone dysfunction.

Main Methods:

Clinical evaluations including family history, color vision testing, and electroretinography (ERG).
Molecular genetic analyses such as linkage analysis and mutation detection in the L-M pigment gene array.

Main Results:

Eighteen families with X-linked retinal disease and cone impairment were studied.
Disease-causing mutations in the L-M opsin gene array were found in six families, including novel deletions and point mutations.
Diverse phenotypes, including blue cone monochromacy (BCM), cone dystrophy, and maculopathy, were associated with different mutations.

Conclusions:

Novel and known mutations within the L-M opsin gene array are linked to X-linked cone-dominated phenotypes.
The L-M opsin gene array can harbor various mutations leading to a range of visual disorders.
Routine genetic analysis of the L-M opsin gene array is recommended for males with X-linked cone-dominated retinal diseases.