Junctional Epidermolysis Bullosa via the LAMC2 Gene
Summary and Pricing
Test Method
Sequencing and CNV Detection via NextGen Sequencing using PG-Select Capture ProbesTest Code | Test Copy Genes | Test CPT Code | Gene CPT Codes Copy CPT Code | Base Price | |
---|---|---|---|---|---|
7725 | LAMC2 | 81479 | 81479,81479 | $990 | Order Options and Pricing |
Pricing Comments
Testing run on PG-select capture probes includes CNV analysis for the gene(s) on the panel but does not permit the optional add on of exome-wide CNV analysis. Any of the NGS platforms allow reflex to other clinically relevant genes, up to whole exome or whole genome sequencing depending upon the base platform selected for the initial test.
An additional 25% charge will be applied to STAT orders. STAT orders are prioritized throughout the testing process.
This test is also offered via a custom panel (click here) on our exome or genome backbone which permits the optional add on of exome-wide CNV or genome-wide SV analysis.
Turnaround Time
3 weeks on average for standard orders or 2 weeks on average for STAT orders.
Please note: Once the testing process begins, an Estimated Report Date (ERD) range will be displayed in the portal. This is the most accurate prediction of when your report will be complete and may differ from the average TAT published on our website. About 85% of our tests will be reported within or before the ERD range. We will notify you of significant delays or holds which will impact the ERD. Learn more about turnaround times here.
Targeted Testing
For ordering sequencing of targeted known variants, go to our Targeted Variants page.
Clinical Features and Genetics
Clinical Features
Junctional epidermolysis bullosa (JEB), a clinically and genetically heterogeneous skin/mucosa separation disorder, is characterized by blister formation induced by minimal mechanical trauma. Mutations in LAMC2 comprise ~9% of pathogenic mutations related to the two major types of JEB (Herlitz JEB, also called neonatal lethal JEB; OMIM#226700) and (Non-Herlitz JEB; OMIM#226650). In Herlitz JEB, blisters occur at birth or neonatal period and are prone to form erosions and granulations in oral, corneal, esophageal and lung tissues, causing restriction of these organs. Patients often die during first year of life due to complications of dehydration, anemia and sepsis. In non-Herlitz JEB, blisters develop relatively late with less involvement from other organs. However, clinical manifestations are highly variable and significantly overlap among different types of epidemolysis bullosa (EB). Therefore, clinically suspected EB patients can be evaluated by skin biopsy to help with clinical diagnosis and direct genetic testing (Fine et al. J Am Acad Derm 58:931-950, 2008; Pfendner et al. GeneReview, 2008; Laimer et al. Dermatol Clin 28:55–60, 2010).
Genetics
LAMC2 codes the γ chain of Laminin 5 protein (Laminin-332), a component of anchoring filaments in basal membrane zone of skin. LAMC2 mutations cause autosomal recessive JEB with complete penetrance. So far, all of the 35 reported LAMC2 mutations are truncating mutations (nonsense, frameshift and splicing); no missense mutations were reported. The nonsense mutation p.Arg95Stop was predominantly seen among Italian patents. Uniparental disomy and chromosome rearrangement have been reported (Takizawa et al. J Invest Dermatology 115:307-311, 2000; Posteraro et al. J Invest Dermatology, 123:639–648, 2004; Pfendner et al, 2008).
Clinical Sensitivity - Sequencing with CNV PG-Select
Detection rate should be high in biopsy confirmed JEB patients with either reduced or absent Laminin5 expression, who have no mutations in LAMB2 or LAMA3.
Testing Strategy
This test provides full coverage of all coding exons of the LAMC2 gene, plus ~10 bases of flanking noncoding DNA. We define full coverage as >20X NGS reads or Sanger sequencing.
Indications for Test
Individuals with clinical features consistent with H-JEB, Non-Herlitz JEB. Individuals diagnosed with skin biopsy by transmission electron microscopy or immunoflurocence staining are preferred. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in LAMC2.
Individuals with clinical features consistent with H-JEB, Non-Herlitz JEB. Individuals diagnosed with skin biopsy by transmission electron microscopy or immunoflurocence staining are preferred. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in LAMC2.
Gene
Official Gene Symbol | OMIM ID |
---|---|
LAMC2 | 150292 |
Inheritance | Abbreviation |
---|---|
Autosomal Dominant | AD |
Autosomal Recessive | AR |
X-Linked | XL |
Mitochondrial | MT |
Diseases
Name | Inheritance | OMIM ID |
---|---|---|
Junctional Epidermolysis Bullosa | AR | 226700 |
Non-Herlitz Junctional Epidermolysis Bullosa | AR | 226650 |
Related Test
Name |
---|
Junctional Epidermolysis Bullosa via the COL17A1 Gene |
Citations
- Fine et al. (2008). "The classification of inherited epidermolysis bullosa (EB): Report of the Third International Consensus Meeting on Diagnosis and Classification of EB." J Am Acad Derm 58(6):931-950. PubMed ID: 18374450
- Laimer et al. Herlitz junctional epidermolysis bullosa. Dermatol Clin 28(1):55-60, 2010. PubMed ID: 19945616
- Pfendner et al. Junctional Epidermolysis Bullosa. GeneReviews, 2008 PubMed ID: 20301304
- Posteraro et al. Laminin-5 mutational analysis in an Italian cohort of patients with junctional epidermolysis bullosa. J Invest Dermatology 123(4):639–648, 2004. PubMed ID: 15373767
- Takizawa et al. Mutation report: complete paternal uniparental isodisomy of chromosome 1: a novel mechanism for Herlitz junctional epidermolysis bullosa. J Invest Dermatology 115(2):307-311, 2000. PubMed ID: 10951251
Ordering/Specimens
Ordering Options
We offer several options when ordering sequencing tests. For more information on these options, see our Ordering Instructions page. To view available options, click on the Order Options button within the test description.
myPrevent - Online Ordering
- The test can be added to your online orders in the Summary and Pricing section.
- Once the test has been added log in to myPrevent to fill out an online requisition form.
- PGnome sequencing panels can be ordered via the myPrevent portal only at this time.
Requisition Form
- A completed requisition form must accompany all specimens.
- Billing information along with specimen and shipping instructions are within the requisition form.
- All testing must be ordered by a qualified healthcare provider.
For Requisition Forms, visit our Forms page
If ordering a Duo or Trio test, the proband and all comparator samples are required to initiate testing. If we do not receive all required samples for the test ordered within 21 days, we will convert the order to the most effective testing strategy with the samples available. Prior authorization and/or billing in place may be impacted by a change in test code.
Specimen Types
ORDER OPTIONS
View Ordering Instructions1) Select Test Type
2) Select Additional Test Options
No Additional Test Options are available for this test.