Clinical Characteristics of Neuronal Intranuclear Inclusion Disease-Related Retinopathy With CGG Repeat Expansions in the NOTCH2NLC Gene

Natsuko Nakamura; Kazushige Tsunoda; Akihiko Mitsutake; Shota Shibata; Tatsuo Mano; Yu Nagashima; Hiroyuki Ishiura; Atsushi Iwata; Tatsushi Toda; Shoji Tsuji; Hiromasa Sawamura

doi:10.1167/iovs.61.11.27

Clinical Characteristics of Neuronal Intranuclear Inclusion Disease-Related Retinopathy With CGG Repeat Expansions in the NOTCH2NLC Gene

Invest Ophthalmol Vis Sci. 2020 Sep 1;61(11):27. doi: 10.1167/iovs.61.11.27.

Authors

Affiliations

¹ Department of Ophthalmology, The University of Tokyo, Tokyo, Japan.
² Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan.
³ Department of Neurology, The University of Tokyo, Tokyo, Japan.
⁴ Department of Molecular Neurology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
⁵ Institute of Medical Genomics, International University of Health and Welfare, Chiba, Japan.

Abstract

Purpose: To report the ocular characteristics of neuronal intranuclear inclusion disease (NIID)-related retinopathy with expansion of the CGG repeats in the NOTCH2NLC gene.

Methods: Seven patients from six families (aged 66-81 years) diagnosed with adult-onset NIID were studied. Ophthalmologic examinations, including the best-corrected visual acuity (BCVA), Goldmann perimetry, fundus photography, fundus autofluorescence (FAF) imaging, optical coherence tomography (OCT), and full-field electroretinography (ERGs), were performed. The expansion of the CGG repeats in the NOTCH2NLC gene was determined.

Results: All patients had an expansion of the CGG repeats (length approximately from 330-520 bp) in the NOTCH2NLC gene. The most common symptoms of the five symptomatic cases were reduced BCVA and night blindness. The other two cases did not have any ocular symptoms. The decimal BCVA varied from 0.15 to 1.2. Goldmann perimetry was constricted in all four cases tested; physiological blind spot was enlarged in two of the cases. The FAF images showed an absence of autofluorescence (AF) around the optic disc in all cases and also showed mild hypo-AF or extinguished AF in the midperiphery. In all cases, the OCT images showed an absence of the ellipsoid zone of the photoreceptors in the peripapillary region, and hyperreflective dots were also present between the retinal ganglion cell layer and outer nuclear layer. The macular region was involved in the late stage of the retinopathy. The full-field ERGs showed rod-cone dysfunction.

Conclusions: Patients with adult-onset NIID with CGG repeats expansions in the NOTCH2NLC gene had similar ophthalmologic features, including rod-cone dysfunction with progressive retinal degeneration in the peripapillary and midperipheral regions. The primary site is most likely the photoreceptors. Because the ocular symptoms are often overlooked due to dementia and occasionally precede the onset of dementia, detailed ophthalmological examinations are important for the early diagnosis of NIID-related retinopathy.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aged
Aged, 80 and over
Electroretinography
Female
Fluorescein Angiography
Follow-Up Studies
Fundus Oculi
Gene Expression Regulation*
Humans
Intranuclear Inclusion Bodies / genetics
Male
Neurodegenerative Diseases / complications*
Neurodegenerative Diseases / diagnosis
Neurodegenerative Diseases / genetics
RNA / genetics
Receptor, Notch2 / biosynthesis
Receptor, Notch2 / genetics*
Retina / metabolism*
Retina / pathology
Retinal Diseases / etiology
Retinal Diseases / genetics*
Retinal Diseases / metabolism
Retrospective Studies
Tomography, Optical Coherence

Substances

NOTCH2 protein, human
Receptor, Notch2
RNA

Supplementary concepts

Neuronal intranuclear inclusion disease