Original articleGenotype and Phenotype of 101 Dutch Patients with Congenital Stationary Night Blindness
Section snippets
Study Population
Patients were referred to Bartiméus by ophthalmologists from hospitals across The Netherlands. Reasons for referral included reduced visual acuity, nystagmus, symptoms of night blindness, or high refractive error at a young age. All patients were Caucasian. On the basis of standard ERG measurements as recommended by the International Society for Clinical Electrophysiology of Vision (ISCEV),22 the patients were diagnosed with CSNB1 or CSNB2. The age of the patients at the time of the ERG was on
DNA Analysis in Patients with CSNB1 and Patients with CSNB2
Figure 2 shows the distribution of the molecular genetic cause of our population of 39 patients with CSNB1 (from 29 families) and 62 patients with CSNB2 (from 43 families). To date, we have found a mutation in 94 patients (93%). In these 94 patients, the genetic diagnosis confirmed the electrophysiologically established diagnosis of CSNB1 or CSNB2. We did not find a mutation in 3 patients with CSNB1 (3 families) and 4 patients with CSNB2 (4 families). The mutations and the frequency of the
Discussion
We diagnosed 39 patients with CSNB1 and 62 patients with CSNB2 on the basis of clinical symptoms and standard ISCEV ERG measurements. Subsequent DNA analysis showed that the NYX (51%) and TRPM1 (26%) genes were the major causes of CSNB1,13 and that X-linked and autosomal recessive inheritance occurred equally in CSNB1 (Fig 2). In contrast, X-linked inheritance was predominant in CSNB2 (89%). The inheritance frequencies hardly changed when based on families instead of individual patients,
Acknowledgments
The authors thank C. C. W. Klaver and J. W. R. Pott for referring patients, and F. P. M. Cremers and K. W Littink for contributions in study design and technical assistance in DNA analysis.
References (32)
- et al.
The electroretinographic diagnosis of the incomplete form of congenital stationary night blindness
Vision Res
(1995) - et al.
Mutations in TRPM1 are a common cause of complete congenital stationary night blindness
Am J Hum Genet
(2009) - et al.
TRPM1 is mutated in patients with autosomal-recessive complete congenital stationary night blindness
Am J Hum Genet
(2009) - et al.
Recessive mutations of the gene TRPM1 abrogate ON bipolar cell function and cause complete congenital stationary night blindness in humans
Am J Hum Genet
(2009) - et al.
Whole-exome sequencing identifies mutations in GPR179 leading to autosomal-recessive complete congenital stationary night blindness
Am J Hum Genet
(2012) - et al.
GPR179 is required for depolarizing bipolar cell function and is mutated in autosomal-recessive complete congenital stationary night blindness
Am J Hum Genet
(2012) - et al.
Mutations in CABP4, the gene encoding the Ca2+-binding protein 4, cause autosomal recessive night blindness
Am J Hum Genet
(2006) - et al.
Clinical variability among patients with incomplete X-linked congenital stationary night blindness and a founder mutation in CACNA1F
Can J Ophthalmol
(2000) - et al.
Beitrag zur Analyse des menschlichen Elektroretinogramms
Ophthalmologica
(1952) - et al.
Congenital stationary night blindness with negative electroretinogram: a new classification
Arch Ophthalmol
(1986)
The photopic electroretinogram in congenital stationary night blindness with myopia
Invest Ophthalmol Vis Sci
A comparison of ERG abnormalities in XLRS and XLCSNB
Doc Ophthalmol
Characteristic ERG-flicker anomaly in incomplete congenital stationary night blindness
Invest Ophthalmol Visual Sci
Variable expressivity in X-linked congenital stationary night blindness
Can J Ophthalmol
Genotype-phenotype correlation in British families with X linked congenital stationary night blindness
Br J Ophthalmol
The complete form of X-linked congenital stationary night blindness is caused by mutations in a gene encoding a leucine-rich repeat protein
Nat Genet
Cited by (0)
Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.
This study was partially funded by ODAS Stichting and Inzicht. The sponsor or funding organization had no role in the design or conduct of this research.