Corneal Dystrophy Panel

  • bpg-method PLUS
  • bpg-method SEQ
  • bpg-method DEL/DUP

Test code: OP1601

The Blueprint Genetics Corneal Dystrophy Panel is a 15 gene test for genetic diagnostics of patients with clinical suspicion of corneal dystrophy.

This panel covers genes associated with autosomal recessive and dominant corneal dystrophies, such as lattice corneal dystrophy, Meesman corneal dystrophy and macular corneal dystrophy.

About Corneal Dystrophy

Corneal dystrophy refers to a heterogeneous group of bilateral genetically determined non-inflammatory corneal diseases that are usually restricted to the cornea. Clinically, the corneal dystrophies can be divided into three groups based the specific location within the cornea. It can affect primarily the corneal epithelium and its basement membrane (superficial corneal dystrophy), the corneal stroma (stromal corneal dystrophy) or Descemet membrane and the corneal endothelium (posterior corneal dystrophy). Different corneal dystrophies are caused by mutations in the CHST6, KRT12, SLC4A11, TCF4, ZEB1 and TGFBI genes and may have an autosomal dominant or autosomal recessive mode of inheritance. Mutations in ZNF469 cause autosomal recessive brittle cornea syndrome, characterized by blue sclerae, corneal rupture after minor trauma, keratoconus or keratoglobus, hyperelasticity of the skin, and hypermobility of the joints. Defects in LCAT are associated with autosomal recessive fish-eye diseasw (familial LCAT deficiency). Prevalence of the corneal dystrophies is variable but these conditions are rare.

Availability

Results in 3-4 weeks. We do not offer a maternal cell contamination (MCC) test at the moment. We offer prenatal testing only for cases where the maternal cell contamination studies (MCC) are done by a local genetic laboratory. Read more: http://blueprintgenetics.com/faqs/#prenatal

Genes in the Corneal Dystrophy Panel and their clinical significance
Gene Associated phenotypes Inheritance ClinVar HGMD
CHST6 Macular dystrophy, corneal AR 10 174
COL5A1 Ehlers-Danlos syndrome AD 43 133
CYP4V2 Retinitis pigmentosa, Bietti crystalline corneoretinal dystrophy AR 30 75
FOXE3 Aphakia, congenital primary, Anterior segment mesenchymal dysgenesis AR/AD 3 21
GJA8 Cataract AD/AR 15 50
KRT12 Meesmann corneal dystrophy AD 8 24
LCAT Lecithin:cholesterol acyltransferase deficiency, Fish-eye disease AR 18 102
LOXHD1 Deafness AR 12 37
MAF Ayme-Gripp syndrome AD 16 16
PITX2 Axenfeld-Rieger syndrome, Ring dermoid of cornea, Iridogoniodysgenesis, Peters anomaly AD 13 85
SLC4A11 Cryohydrocytosis AD 21 93
TCF4 Corneal dystrophy, Fuchs endothelial, Pitt-Hopkins syndrome AD 51 129
TGFBI Corneal dystrophy, Avellino, Corneal dystrophy, Thiel-Behnke, Corneal dystrophy, Groenouw, Corneal dystrophy, epithelial basement membrane, Corneal dystrophy of Bowman layer, Corneal dystrophy, Corneal dystrophy, Reis-Bucklers AD 13 70
ZEB1 Corneal dystrophy, Fuchs endothelial, Corneal dystrophy, posterior polymorphous AD 4 50
ZNF469 Brittle cornea syndrome AR 31 35

*Some regions of the gene are duplicated in the genome leading to limited sensitivity within the regions. Thus, low-quality variants are filtered out from the duplicated regions and only high-quality variants confirmed by other methods are reported out. Read more.

Gene, refers to HGNC approved gene symbol; Inheritance to inheritance patterns such as autosomal dominant (AD), autosomal recessive (AR) and X-linked (XL); ClinVar, refers to a number of variants in the gene classified as pathogenic or likely pathogenic in ClinVar (http://www.ncbi.nlm.nih.gov/clinvar/); HGMD, refers to a number of variants with possible disease association in the gene listed in Human Gene Mutation Database (HGMD, http://www.hgmd.cf.ac.uk/ac/). The list of associated (gene specific) phenotypes are generated from CDG (http://research.nhgri.nih.gov/CGD/) or Orphanet (http://www.orpha.net/) databases.

Gene Genomic location HG19 HGVS RefSeq RS-number Comment Reference
COL5A1 Chr9:137686903 c.2701-25T>G NM_000093.4 rs765079080
LCAT Chr16:67976512 c.524-22T>C NM_000229.1 rs794726664

The strengths of this test include:

  • Blueprint Genetics is one of the few laboratories worldwide with CAP and ISO-15189 accreditation for NGS panels and CLIA certification
  • Superior sequencing quality
  • Careful selection of genes based on current literature, our experience and the most current mutation databases
  • Transparent and easy access to quality and performance data at the patient level that are accessible via our Nucleus portal
  • Transparent and reproducible analytical validation for each panel (see Test performance section; for complete details, see our Analytic Validation)
  • Sequencing and high resolution del/dup analysis available in one test
  • Inclusion of non-coding disease causing variants where clinically indicated (please see individual Panel descriptions)
  • Interpretation of variants following ACMG variant classification guidelines
  • Comprehensive clinical statement co-written by a PhD geneticist and a clinician specialist

 

This test does not detect the following:

  • Complex inversions
  • Gene conversions
  • Balanced translocations
  • Mitochondrial DNA variants
  • Variants in regulatory or non-coding regions of the gene unless otherwise indicated (please see Non-coding disease causing variants covered by the panel). This mean for instance intronic variants locating deeper than 15 nucleotides from the exon-intron boundary.

 

This test may not reliably detect the following:

  • Low level mosaicism
  • Stretches of mononucleotide repeats
  • Indels larger than 50bp
  • Single exon deletions or duplications
  • Variants within pseudogene regions/duplicated segments
  • Disorders caused by long repetitive sequences (e.g. trinucleotide repeat expansions)

 

The sensitivity of this test may be reduced if DNA is extracted by a laboratory other than Blueprint Genetics.

For additional information, please refer to the Test performance section and see our Analytic Validation.

Blueprint Genetics offers a comprehensive Corneal Dystrophy Panel that covers classical genes associated with corneal dystrophy, fish-eye disease, Fuchs endothelial corneal dystrophy, lattice corneal dystrophy, macular corneal dystrophy and Meesmann corneal dystrophy. The genes are carefully selected based on the existing scientific evidence, our experience and most current mutation databases. Candidate genes are excluded from this first-line diagnostic test. The test does not recognise balanced translocations or complex inversions, and it may not detect low-level mosaicism. The test should not be used for analysis of sequence repeats or for diagnosis of disorders caused by mutations in the mitochondrial DNA.

Analytical validation is a continuous process at Blueprint Genetics. Our mission is to improve the quality of the sequencing process and each modification is followed by our standardized validation process. Average sensitivity and specificity in Blueprint NGS Panels is 99.3% and 99.9% for detecting SNPs. Sensitivity to for indels vary depending on the size of the alteration: 1-10bps (96.0%), 11-20 bps (88.4%) and 21-30 bps (66.7%). The longest detected indel was 46 bps by sequence analysis. Detection limit for Del/Dup (CNV) analysis varies through the genome depending on exon size, sequencing coverage and sequence content. The sensitivity is 71.5% for single exon deletions and duplications and 99% for three exons’ deletions and duplications. We have validated the assays for different starting materials including EDTA-blood, isolated DNA (no FFPE) and saliva that all provide high-quality results. The diagnostic yield varies substantially depending on the used assay, referring healthcare professional, hospital and country. Blueprint Genetics’ Plus Analysis (Seq+Del/Dup) maximizes the chance to find molecular genetic diagnosis for your patient although Sequence Analysis or Del/Dup Analysis may be cost-effective first line test if your patient’s phenotype is suggestive for a specific mutation profile.

The sequencing data generated in our laboratory is analyzed with our proprietary data analysis and annotation pipeline, integrating state-of-the art algorithms and industry-standard software solutions. Incorporation of rigorous quality control steps throughout the workflow of the pipeline ensures the consistency, validity and accuracy of results. The highest relevance in the reported variants is achieved through elimination of false positive findings based on variability data for thousands of publicly available human reference sequences and validation against our in-house curated mutation database as well as the most current and relevant human mutation databases. Reference databases currently used are the 1000 Genomes Project (http://www.1000genomes.org), the NHLBI GO Exome Sequencing Project (ESP; http://evs.gs.washington.edu/EVS), the Exome Aggregation Consortium (ExAC; http://exac.broadinstitute.org), ClinVar database of genotype-phenotype associations (http://www.ncbi.nlm.nih.gov/clinvar) and the Human Gene Mutation Database (http://www.hgmd.cf.ac.uk). The consequence of variants in coding and splice regions are estimated using the following in silico variant prediction tools: SIFT (http://sift.jcvi.org), Polyphen (http://genetics.bwh.harvard.edu/pph2/), and Mutation Taster (http://www.mutationtaster.org).

Through our online ordering and statement reporting system, Nucleus, the customer can access specific details of the analysis of the patient. This includes coverage and quality specifications and other relevant information on the analysis. This represents our mission to build fully transparent diagnostics where the customer gains easy access to crucial details of the analysis process.

In addition to our cutting-edge patented sequencing technology and proprietary bioinformatics pipeline, we also provide the customers with the best-informed clinical report on the market. Clinical interpretation requires fundamental clinical and genetic understanding. At Blueprint Genetics our geneticists and clinicians, who together evaluate the results from the sequence analysis pipeline in the context of phenotype information provided in the requisition form, prepare the clinical statement. Our goal is to provide clinically meaningful statements that are understandable for all medical professionals, even without training in genetics.

Variants reported in the statement are always classified using the Blueprint Genetics Variant Classification Scheme modified from the ACMG guidelines (Richards et al. 2015), which has been developed by evaluating existing literature, databases and with thousands of clinical cases analyzed in our laboratory. Variant classification forms the corner stone of clinical interpretation and following patient management decisions. Our statement also includes allele frequencies in reference populations and in silico predictions. We also provide PubMed IDs to the articles or submission numbers to public databases that have been used in the interpretation of the detected variants. In our conclusion, we summarize all the existing information and provide our rationale for the classification of the variant.

A final component of the analysis is the Sanger confirmation of the variants classified as likely pathogenic or pathogenic. This does not only bring confidence to the results obtained by our NGS solution but establishes the mutation specific test for family members. Sanger sequencing is also used occasionally with other variants reported in the statement. In the case of variant of uncertain significance (VUS) we do not recommend risk stratification based on the genetic finding. Furthermore, in the case VUS we do not recommend use of genetic information in patient management or genetic counseling. For some cases Blueprint Genetics offers a special free of charge service to investigate the role of identified VUS.

We constantly follow genetic literature adapting new relevant information and findings to our diagnostics. Relevant novel discoveries can be rapidly translated and adopted into our diagnostics without delay. These processes ensure that our diagnostic panels and clinical statements remain the most up-to-date on the market.

Find more info in Support

Choose an analysis method

$ $ 1400
$ $ 1000
$ $ 1600
Total $
Order now

ICD & CPT codes

CPT codes

SEQ 81479
DEL/DUP 81479


ICD codes

Commonly used ICD-10 codes when ordering the Corneal Dystrophy Panel

ICD-10 Disease
H18.50 Corneal dystrophy

Accepted sample types

  • EDTA blood, min. 1 ml
  • Purified DNA, min. 5μg
  • Saliva (Oragene DNA OG-500 kit)

Label the sample tube with your patient’s name, date of birth and the date of sample collection.

Note that we do not accept DNA samples isolated from formalin-fixed paraffin-embedded (FFPE) tissue.

Subscribe to our newsletter