[Skip to Content]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address Please contact the publisher to request reinstatement.
[Skip to Content Landing]
November 1993

Dominant Retinitis Pigmentosa Associated With Two Rhodopsin Gene Mutations: Leu-40-Arg and an Insertion Disrupting the 5′-Splice Junction of Exon 5

Author Affiliations

From the Departments of Clinical Ophthalmology (Drs Kim, Jay, and Bird), Molecular Genetics (Ms Al-Maghtheh and Dr Bhattacharya), Visual Sciences (Dr Fitzke), and Electrophysiology and Psychophysics (Dr Arden), Institute of Ophthalmology and Moorfields Eye Hospital, London, England.

Arch Ophthalmol. 1993;111(11):1518-1524. doi:10.1001/archopht.1993.01090110084030

Objective:  To determine the phenotypes of two families in which retinitis pigmentosa cosegregates with a rhodopsin (RHO) gene mutation: a leucine-to-arginine change at codon 40 (Leu-40-Arg) in one family, and a 150-base pair insertion that disrupts the RHO 5′-splice junction of exon 5 in another.

Patients:  Three affected members of each family.

Results:  The Leu-40-Arg mutation was associated with the onset of night blindness in the first decade of life. By the fourth decade, severe retinal functional loss was evident on dark-adapted static threshold perimetry, and electroretinographic responses were absent or barely detectable. In contrast, the RHO 150-base pair insertion was associated with the later onset of mild night vision difficulties; in two individuals, mild night vision difficulties were first noticed in the second decade while a third, a 25-year-old woman, was asymptomatic. Dark-adapted static threshold perimetry of this latter individual revealed a "regional" or class 2 pattern of retinal functional loss associated with equal loss of rod and cone electroretinographic responses.

Conclusion:  The RHO Leu-40-Arg mutation causes symptomatic retinal dysfunction by the end of the first decade while the insertion disrupting the 5′-splice junction of RHO exon 5 causes later onset "regional" or class 2 retinal dysfunction.