Diagnostics

Learn how our advanced genetic tests are revolutionizing health

Corneal Dystrophies Panel

The Corneal Dystrophies Panel is a comprehensive next-generation sequencing (NGS) panel that can be used to confirm a clinical diagnosis of corneal dystrophy or identify at-risk individuals.

Corneal dystrophies are a heterogenous group of disorders characterized by a loss of corneal transparency and impaired refraction. Corneal dystrophies are non-inflammatory eyes disorders which are typically caused by accumulations of deposits in layers of the cornea. As the disease progresses, visual acuity is reduced and can lead to vision loss and blindness.

Included Disorders

This panel includes genes associated with:

  • Avellino corneal dystrophy
  • Thiel-Behnke corneal dystrophy
  • Groenouw corneal dystrophy
  • Bietti crystalline corneoretinal dystrophy
  • Axenfeld-Rieger syndrome
  • Anterior segment dysgenesis
  • Congenital cataract
  • Fish-eye disease
  • Norum disease
  • Ayme-Gripp syndrome
  • Keratoconus
  •  

    Prevalence

    The overall prevalence of corneal dystrophies has been estimated to be approximately in 1 in 1,000 (Musch et al, 2011; Lee et al, 2010), although they may be more frequent in some populations.

    Inheritance and Penetrance

    Corneal dystrophies are inherited in autosomal dominant and autosomal recessive fashions. Penetrance is typically high.

    Clinical Sensitivity

    Clinical sensitivity is highly dependent on a patient’s specific phenotype as these conditions demonstrate significant genetic heterogeneity. One study found that pathogenic TGFBI variants were found in 80% (50/61) of corneal dystrophy patients (Munier et al, 2002).

    Methodology and Analytical Sensitivity

    Next-generation sequencing technology is used to test clinically relevant portions of each gene, including coding exons, adjacent flanking bases, and selected introns/noncoding variants. Pathogenic and likely pathogenic variants are confirmed by orthogonal methods. Copy number variants, including intragenic deletions and duplications are detected to a resolution of a single exon. To request analysis of a specific single exon copy number variant, please contact our Client Services team prior to ordering. Analytical sensitivity and specificity of the assay is >99%.

    Indications for Testing

    • Confirmation of a clinical diagnosis
    • Risk assessment for asymptomatic family members of proband with molecular diagnosis of early onset glaucoma

    Included Genes (8)

    CYP4V2 FOXE3 GJA8 LCAT MAF PITX2 TGFBI VSX1

     

    References

    1. Munier FL, Frueh BE, Othenin-girard P, et al. BIGH3 mutation spectrum in corneal dystrophies. Invest Ophthalmol Vis Sci. 2002;43(4):949-54.
    2. Musch DC, Niziol LM, Stein JD, Kamyar RM, Sugar A. Prevalence of corneal dystrophies in the United States: estimates from claims data. Invest Ophthalmol Vis Sci. 2011;52(9):6959-63.
    3. Lee JH, Cristol SM, Kim WC, et al. Prevalence of granular corneal dystrophy type 2 (Avellino corneal dystrophy) in the Korean population. Ophthalmic Epidemiol. 2010;17(3):160-5.