TULP1-Associated Disorders via the TULP1 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 | |
---|---|---|---|---|---|
8451 | TULP1 | 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
Retinitis pigmentosa (RP, OMIM 268000) and Leber congenital amaurosis (LCA, OMIM 204000) are inherited degenerative diseases of the retina. RP is characterized by night blindness, with age of onset varying from childhood to middle age, and progressing to constriction of the peripheral visual field and eventual loss of central vision. LCA is characterized by bilateral congenital blindness. Several clinical features of LCA overlap with those of RP. These include attenuated retinal vessels, abnormal electroretinographic (ERG) findings, and a variable amount of retinal pigmentation (Perrault et al. Nat Genet 14:461-464, 1996; Daiger et al. Arch Ophthalmol 125:151-158, 2007; Gu et al. J Med Genet 36:705-707, 1999). Both LCA and RP are clinically and genetically heterogeneous, and the diagnostic boundary separating autosomal recessive RP (AR-RP) and LCA is not clear (Rivolta et al. Hum Mol Genet 11:1219-1227, 2002).
Genetics
Retinitis pigmentosa (RP) is either sporadic or familial with various modes of inheritance, including Mendelian, mitochondrial, or digenic. Autosomal recessive (AR-RP) is the most severe form of the disease. Leber congenital amaurosis (LCA) is inherited as an autosomal recessive trait in the vast majority of patients. To date, 25 and 14 genes have been implicated in AR-RP and LCA, respectively (Daiger et al. Arch Ophthalmol 125:151-158, 2007; den Hollander et al. Prog Retin Eye Res 27:391-419, 2008). The clinical overlap between AR-RP and LCA is illustrated by the involvement of six genes in both conditions. These include the TULP1 gene (Hagstrom et al. Nat Genet 18:174-176, 1998; Banerjee et al. Nat Genet 18:177-179, 1998). Over 23 different TULP1 variants have been reported in patients with AR-RP (RP14, OMIM 600132) including missense, nonsense, splicing, and small deletions or insertions. AR-RP patients with TULP1 variants presented with a severe phenotype and variable age of onset. Four TULP1 variants were identified in three patients with LCA (OMIM 204000). One patient was compound heterozygote for a splice variant and a nonsense variant, and the other two were homozygous for two distinct nonsense variants (Hanein et al. Hum Mutat 23:306-317, 2004).
The TULP1 protein is primarily expressed in the retina.
Clinical Sensitivity - Sequencing with CNV PGxome
TULP1 variants account for up to 2% of all AR-RP patients (den Hollander et al. Invest Ophthalmol Vis Sci 48:5690-5698, 2007) and ~ 1.7% of LCA patients (Hanein et al. Hum Mutat 23:306-317, 2004).
Testing Strategy
This test provides full coverage of all coding exons of the TULP1 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 LCA are candidates. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in TULP1.
Patients with AR-RP and LCA are candidates. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in TULP1.
Gene
Official Gene Symbol | OMIM ID |
---|---|
TULP1 | 602280 |
Inheritance | Abbreviation |
---|---|
Autosomal Dominant | AD |
Autosomal Recessive | AR |
X-Linked | XL |
Mitochondrial | MT |
Diseases
Name | Inheritance | OMIM ID |
---|---|---|
Leber Congenital Amaurosis 15 | AR | 613843 |
Retinitis Pigmentosa 14 | AR | 600132 |
Related Tests
Name |
---|
Leber Congenital Amaurosis Panel |
Retinitis Pigmentosa Panel |
Citations
- Banerjee, P., et.al. (1998). "TULP1 mutation in two extended Dominican kindreds with autosomal recessive retinitis pigmentosa." Nat Genet 18(2): 177-9. PubMed ID: 9462751
- Daiger et al. 2007. PubMed ID: 17296890
- den Hollander AI, Roepman R, Koenekoop RK, Cremers FPM. 2008. Leber congenital amaurosis: genes, proteins and disease mechanisms. Prog Retin Eye Res 27: 391–419. PubMed ID: 18632300
- den Hollander, A. I., et.al. (2007). "Identification of novel mutations in patients with Leber congenital amaurosis and juvenile RP by genome-wide homozygosity mapping with SNP microarrays." Invest Ophthalmol Vis Sci 48(12): 5690-8. PubMed ID: 18055821
- Gu S. et al. 1999. Journal of Medical Genetics. 36: 705-7. PubMed ID: 10507729
- Hagstrom, S. A., et.al. (1998). "Recessive mutations in the gene encoding the tubby-like protein TULP1 in patients with retinitis pigmentosa." Nat Genet 18(2): 174-6. PubMed ID: 9462750
- Hanein, S., et.al. (2004). "Leber congenital amaurosis: comprehensive survey of the genetic heterogeneity, refinement of the clinical definition, and genotype-phenotype correlations as a strategy for molecular diagnosis." Hum Mutat 23(4): 306-317. PubMed ID: 15024725
- Perrault I, Rozet JM, Calvas P, Gerber S, Camuzat A, Dollfus H, Châtelin S, Souied E, Ghazi I, Leowski C, Bonnemaison M, Paslier D Le, et al. 1996. Retinal-specific guanylate cyclase gene mutations in Leber’s congenital amaurosis. Nat. Genet. 14: 461–464. PubMed ID: 8944027
- Rivolta, C., et.al. (2002). "Retinitis pigmentosa and allied diseases: numerous diseases, genes, and inheritance patterns." Hum Mol Genet 11(10): 1219-27. PubMed ID: 12015282
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.