Clinical features of achromatopsia in Swedish patients with defined genotypes

@article{Eksandh2002ClinicalFO,
  title={Clinical features of achromatopsia in Swedish patients with defined genotypes},
  author={Louise Eksandh and Susanne Kohl and Bernd Wissinger},
  journal={Ophthalmic Genetics},
  year={2002},
  volume={23},
  pages={109 - 120}
}
Purpose: To describe the clinical phenotype, with emphasis on the electrophysiological findings, of patients with autosomal recessive rod monochromacy (RM) and defined mutations in the CNGA3 / CNGB3 genes. Methods: RM patients from eight different families were included in the study. Their genotypes were determined by DNA sequencing and/or RFLP analysis of PCR-amplified genomic segments of the CNGA3 and CNGB3 genes. For comparison, we investigated one patient with blue-cone monochromacy (BCM… 

Genotypes and phenotypes of genes associated with achromatopsia: A reference for clinical genetic testing

TLDR
Genotype–phenotype analysis of six achromatopsia-related genes will be useful in drafting guidelines for the clinical genetic diagnostic application for the investigated genes, and PPVs in the six genes were identified in various inherited retinal degeneration diseases.

Progressive cone dystrophy associated with mutation in CNGB3.

PURPOSE To determine the molecular basis for phenotypic variability in a three-generation consanguineous family containing a single individual with complete achromatopsia and three individuals with

CNGB3 mutations account for 50% of all cases with autosomal recessive achromatopsia

TLDR
CNGB3/ACHM3 locus on chromosome 8q21 is the major locus for achromatopsia in patients of European origin or descent, and mutations in the CNGB3 gene are responsible for approximately 50% of all patients with achrom atopsia.

CNGA3 mutations in two United Arab Emirates families with achromatopsia

TLDR
Achromatopsia in these two United Arab Emirates families results from two different mutations in CNGA3, demonstrating a complex molecular pathology in this large family.

[Molecular genetic findings in patients with congenital cone dysfunction. Mutations in the CNGA3, CNGB3, or GNAT2 genes].

TLDR
In patients with congenital cone dysfunction without cone function in the ERG, an analysis of the CNGA3, CNGB3, or GNAT2 gene is advisable; in contrast, patients with residual cone function did not show clear association with mutations in one of the three genes.

Compound heterozygous CNGA3 mutations (R436W, L633P) in a Japanese patient with congenital achromatopsia

TLDR
To the authors' knowledge, this is the first report of a Japanese complete achromat with CNGA3 mutations, and of any patient with a missense mutation within the CLZ domain, and the outcome suggests low frequency (7%, 1/14) of CN GA3 mutations in Japanese patients.

Achromatopsia caused by novel mutations in both CNGA3 and CNGB3

TLDR
Current estimates suggest that mutations in CNGB3 account for 40–50% of achromatopsia,14 with mutations inCNGA3 contributing a further 20%.5 There is therefore a significant proportion of patients for whom neither CNGA3 norCNGB3 mutations can be found, and GNAT2 is the third gene to be implicated in achrom atopsia.

Clinical heterogeneity between two Japanese siblings with congenital achromatopsia

TLDR
Two siblings with congenital achromatopsia are described, who exhibit different ophthalmic phenotypes, and the brother remains hyperopia and has exhibited no specific retinal findings until age 18 years.

CNGB3 achromatopsia with progressive loss of residual cone function and impaired rod-mediated function.

TLDR
Foveomacular atrophy can occur in CNGB3-affected subjects, and even heterozygous carriers can exhibit maculopathy, and some retain residual function into middle age and then progressively lose even this remnant.

Cone dystrophy phenotype associated with a frameshift mutation (M280fsX291) in the α-subunit of cone specific transducin (GNAT2)

TLDR
Mutation in the α-subunit of cone specific transducin (GNAT2) is characterised by an infantile onset cone dystrophy, which some affected individuals may show deterioration of visual acuity with time.

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