Congenital stationary night blindness

Congenital stationary night blindness
Malfunction in transmission from the photoreceptors in the outer nuclear layer to bipolar cells in the inner nuclear layer underlies CSNB.
SpecialtyOphthalmology Edit this on Wikidata

Congenital stationary night blindness (CSNB) is a rare non-progressive retinal disorder. People with CSNB often have difficulty adapting to low light situations due to impaired photoreceptor transmission. These patients may also have reduced visual acuity, myopia, nystagmus, fundus abnormalities, and strabismus.[1][2] CSNB has two forms -- complete, also known as type-1 (CSNB1), and incomplete, also known as type-2 (CSNB2), which are distinguished by the involvement of different retinal pathways. In CSNB1, downstream neurons called bipolar cells are unable to detect neurotransmission from photoreceptor cells. CSNB1 can be caused by mutations in various genes involved in neurotransmitter detection, including NYX. In CSNB2, the photoreceptors themselves have impaired neurotransmission function; this is caused primarily by mutations in the gene CACNA1F, which encodes a voltage-gated calcium channel important for neurotransmitter release. CSNB has been identified in horses and dogs as the result of mutations in TRPM1 (Horse, "LP")[3], GRM6 (Horse, "CSNB2")[4], and LRIT3 (Dog, CSNB)[5].

Congenital stationary night blindness (CSNB) can be inherited in an X-linked, autosomal dominant, or autosomal recessive pattern, depending on the genes involved.

Two forms of CSNB can also affect horses, one linked to the leopard complex of equine coat colors and the other found in certain horse breeds. Both are autosomal recessives.[6][7]

  1. ^ Bai, Dong'e; Guo, Ruru; Huang, Dandan; Ji, Jian; Liu, Wei (2024-03-15). "Compound heterozygous mutations in GRM6 causing complete Schubert-Bornschein type congenital stationary night blindness". Heliyon. 10 (5): e27039. Bibcode:2024Heliy..1027039B. doi:10.1016/j.heliyon.2024.e27039. ISSN 2405-8440. PMC 10907788. PMID 38434377.
  2. ^ Zeitz, Christina; Robson, Anthony G.; Audo, Isabelle (2015-03-01). "Congenital stationary night blindness: An analysis and update of genotype–phenotype correlations and pathogenic mechanisms". Progress in Retinal and Eye Research. 45: 58–110. doi:10.1016/j.preteyeres.2014.09.001. ISSN 1350-9462. PMID 25307992.
  3. ^ Bellone RR, Holl H, Setaluri V, Devi S, Maddodi N, Archer S, et al. (2013-10-22). "Evidence for a retroviral insertion in TRPM1 as the cause of congenital stationary night blindness and leopard complex spotting in the horse". PLOS ONE. 8 (10): e78280. Bibcode:2013PLoSO...878280B. doi:10.1371/journal.pone.0078280. PMC 3805535. PMID 24167615.
  4. ^ Hack YL, Crabtree EE, Avila F, Sutton RB, Grahn R, Oh A, et al. (March 2021). "Whole-genome sequencing identifies missense mutation in GRM6 as the likely cause of congenital stationary night blindness in a Tennessee Walking Horse". Equine Veterinary Journal. 53 (2): 316–323. doi:10.1111/evj.13318. PMID 32654228. S2CID 220500585.
  5. ^ Das RG, Becker D, Jagannathan V, Goldstein O, Santana E, Carlin K, et al. (October 2019). "Genome-wide association study and whole-genome sequencing identify a deletion in LRIT3 associated with canine congenital stationary night blindness". Scientific Reports. 9 (1): 14166. Bibcode:2019NatSR...914166D. doi:10.1038/s41598-019-50573-7. PMC 6775105. PMID 31578364.
  6. ^ "Appaloosa Panel 2 | Veterinary Genetics Laboratory". vgl.ucdavis.edu. Retrieved 11 October 2022.
  7. ^ "Congenital Stationary Night Blindness (CSNB2) in Tennessee Walking Horses | Veterinary Genetics Laboratory". vgl.ucdavis.edu. Retrieved 11 October 2022.