Preferred Label : Night blindness, congenital stationary, type 1a;
Symbol : CSNB1A;
CISMeF acronym : CSNB1A; NBM1;
Type : Phenotype, molecular basis known;
Alternative titles and symbols : Csnb, complete, X-linked; Night blindness, congenital stationary, with myopia; Myopia-night blindness; HEMERALOPIA-MYOPIA; NBM1;
Included titles and symbols : Nyctalopia;
Description : Congenital stationary night blindness (CSNB) is a clinically and genetically heterogeneous
group of nonprogressive retinal disorders that can be characterized by impaired night
vision, decreased visual acuity, nystagmus, myopia, and strabismus. CSNB can be classified
into 2 groups based on electroretinography (ERG) findings: the Schubert-Bornschein
type is characterized by an ERG in which the b-wave is smaller than the a-wave, whereas
the Riggs type is defined by proportionally reduced a- and b-waves. In addition, Schubert-Bornschein
CSNB is associated with decreased visual acuity, myopia, and nystagmus, whereas in
Riggs CSNB patients have visual acuity within the normal range and no symptoms of
myopia and/or nystagmus (summary by Riazuddin et al., 2010). Additionally, Schubert-Bornschein
CSNB can be subdivided into 'complete' and 'incomplete' forms (summary by Riazuddin
et al., 2010). Van Genderen et al. (2009) noted that standard flash ERG distinguishes
a 'complete' form, also known as type 1 CSNB, from an 'incomplete' form, also known
as type 2 CSNB (see CSNB2A, 300071). The complete form is characterized by the complete
absence of rod pathway function, whereas the incomplete form is due to impaired rod
and cone pathway function. Complete CSNB results from postsynaptic defects in depolarizing
or ON bipolar cell signaling, whereas the hyperpolarizing or OFF bipolar cell pathway
is intact. - Genetic Heterogeneity of Congenital Stationary Night Blindness Autosomal
recessive forms of complete CSNB have been reported: CSNB1B (257270), caused by mutation
in the GRM6 gene (604096); CSNB1C (613216), caused by mutation in the TRPM1 gene (603576);
CSNB1D (613830), caused by mutation in the SLC24A1 gene (603617); and CSNB1E (614565),
caused by mutation in the GPR179 gene (614515). Autosomal dominant forms of complete
CSNB that have been reported include CSNBAD1 (610445), caused by mutation in the RHO
gene (180380);;
Inheritance : X-linked recessive;
Molecular basis : Caused by mutation in the nyctalopin gene (NYX, 300278.0001);
Prefixed ID : #310500;
Origin ID : 310500;
UMLS CUI : C3495587;
Automatic exact mappings (from CISMeF team)
- Broader ORDO disease(s)
- Currated CISMeF NLP mapping
- DO Cross reference
- Genes related to phenotype
- HPO term(s)
- ORDO concept(s)
- Semantic type(s)
- UMLS correspondences (same concept)
- Validated automatic mappings to NTBT
