Retinitis Pigmentosa via the PDE6A Gene
Summary and Pricing
Test Method
Exome Sequencing with CNV DetectionTest Code | Test Copy Genes | Test CPT Code | Gene CPT Codes Copy CPT Code | Base Price | |
---|---|---|---|---|---|
11557 | PDE6A | 81479 | 81479,81479 | $990 | Order Options and Pricing |
Pricing Comments
Our favored testing approach is exome based NextGen sequencing with CNV analysis. This will allow cost effective reflexing to PGxome or other exome based tests. However, if full gene Sanger sequencing is desired for STAT turnaround time, insurance, or other reasons, please see link below for Test Code, pricing, and turnaround time information. If the Sanger option is selected, CNV detection may be ordered through Test #600.
An additional 25% charge will be applied to STAT orders. STAT orders are prioritized throughout the testing process.
Click here for costs to reflex to whole PGxome (if original test is on PGxome Sequencing platform).
Click here for costs to reflex to whole PGnome (if original test is on PGnome Sequencing platform).
The Sanger Sequencing method for this test is NY State approved.
For Sanger Sequencing click here.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
Nonsyndromic retinitis pigmentosa (RP, OMIM # 268000) is a large group of inherited degenerative diseases of the retina characterized by abnormalities of the photoreceptors or the retinal pigment epithelium. It is a progressive disease. Symptoms usually begin with night blindness, progressing to constriction of the peripheral visual field with eventual loss of central vision. The age of onset varies from childhood to middle age (Gu et al. J Med Genet 36:705-707, 1999). The clinical hallmarks are an abnormal fundus with bone-spicule deposits and attenuated retinal vessels, abnormal electroretinographic findings, and reduced visual fields (Daiger et al. Arch Ophthalmol 125:151-158, 2007). RP affects 1 in 3,000 people worldwide (Farrar et al. EMBO J 21:857-864, 2002). Genetic abnormalities are the primary cause of RP, which affects all ethnic groups.
Genetics
Retinitis pigmentosa (RP) is genetically and clinically heterogeneous (Koenekoopet al. Clin Experiment Ophthalmol 35:473-485, 2007). At least four distinct subgroups are recognized on the basis of the mode of inheritance and age of onset. These include autosomal dominant (AD-RP), autosomal recessive (AR-RP), X-linked, and digenic (Kajiwaraet al. Science 264:1604-1608, 1994). In addition, RP can be inherited as a mitochondrial trait (Manserghet al. Am J Hum Genet 64:971-985, 1999). Genetic heterogeneity is documented within each subgroup. Currently, 23 genes have been implicated with AR-RP. These include the PDE6A gene (Huang et al. Nat Genet 11:468-471, 1995). Thirteen different PDE6A variants have been implicated in AR-RP. Although missense variants were the most common, nonsense, splicing and small insertions were also reported and included both compound heterozygous and homozygous variants in families with or without apparent history of consanguinity (Dryja et al. Invest Ophthalmol Vis Sci 40:1859-1865, 1999; Riazuddin et al. Mol Vis 12:1283-1291, 2006). The PDE6A gene encodes the alpha subunit of the rod phosphodiesterase, a key enzyme in phototransduction.
Clinical Sensitivity - Sequencing with CNV PGxome
Variants in the PDE6A gene account for ~4% of patients with AR-RP (Dryja et al. Invest Ophthalmol Vis Sci 40:1859-1865, 1999).
Testing Strategy
This test provides full coverage of all coding exons of the PDE6A gene plus 10 bases of flanking noncoding DNA in all available transcripts along with other non-coding regions in which pathogenic variants have been identified at PreventionGenetics or reported elsewhere. We define full coverage as >20X NGS reads or Sanger sequencing. PGnome panels typically provide slightly increased coverage over the PGxome equivalent. PGnome sequencing panels have the added benefit of additional analysis and reporting of deep intronic regions (where applicable).
Dependent on the sequencing backbone selected for this testing, discounted reflex testing to any other similar backbone-based test is available (i.e., PGxome panel to whole PGxome; PGnome panel to whole PGnome).
Indications for Test
Patients with AR-RP and heterozygote carriers. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in PDE6A.
Patients with AR-RP and heterozygote carriers. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in PDE6A.
Gene
Official Gene Symbol | OMIM ID |
---|---|
PDE6A | 180071 |
Inheritance | Abbreviation |
---|---|
Autosomal Dominant | AD |
Autosomal Recessive | AR |
X-Linked | XL |
Mitochondrial | MT |
Disease
Name | Inheritance | OMIM ID |
---|---|---|
Retinitis Pigmentosa 43 | 613810 |
Citations
- Daiger et al. 2007. PubMed ID: 17296890
- Dryja, T. P., et.al. (1999). "Frequency of mutations in the gene encoding the alpha subunit of rod cGMP-phosphodiesterase in autosomal recessive retinitis pigmentosa." Invest Ophthalmol Vis Sci 40(8): 1859-65. PubMed ID: 10393062
- Farrar, G. J., et.al. (2002). "On the genetics of retinitis pigmentosa and on mutation-independent approaches to therapeutic intervention." Embo J 21(5): 857-64. PubMed ID: 11867514
- Gu S. et al. 1999. Journal of Medical Genetics. 36: 705-7. PubMed ID: 10507729
- Huang, S. H., et.al. (1995). "Autosomal recessive retinitis pigmentosa caused by mutations in the alpha subunit of rod cGMP phosphodiesterase." Nat Genet 11(4): 468-71. PubMed ID: 7493036
- Kajiwara, K. et.al. (1994). "Digenic retinitis pigmentosa due to mutations at the unlinked peripherin/RDS and ROM1 loci." Science 264(5165): 1604-1608. PubMed ID: 8202715
- Koenekoop, R. K., et.al. (2007). "Genetic testing for retinal dystrophies and dysfunctions: benefits, dilemmas and solutions." Clin Experiment Ophthalmol 35(5): 473-85. PubMed ID: 17651254
- Mansergh, F. C., et.al. (1999). "Retinitis pigmentosa and progressive sensorineural hearing loss caused by a C12258A mutation in the mitochondrial MTTS2 gene." Am J Hum Genet 64(4): 971-85. PubMed ID: 10090882
- Riazuddin, S. A., et.al. (2006). "Mutations in the gene encoding the alpha-subunit of rod phosphodiesterase in consanguineous Pakistani families." Mol Vis 12: 1283-91. PubMed ID: 17110911
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
Specimen Requirements and Shipping Details
PGxome (Exome) Sequencing Panel
PGnome (Genome) Sequencing Panel
ORDER OPTIONS
View Ordering Instructions1) Select Test Type
2) Select Additional Test Options
No Additional Test Options are available for this test.