Renal Hypomagnesemia 5 via the CLDN19 Gene
Summary and Pricing 
Test Method
Exome Sequencing with CNV Detection
| Test Code | Test Copy Genes | Test CPT Code | Gene CPT Codes Copy CPT Code | Base Price | |
|---|---|---|---|---|---|
| 9039 | CLDN19 | 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
Renal hypomagnesemia 5 (HOMG5) is a type of familial hypomagnesemia with hypercalciuria and nephrocalcinosis particularly associated with severe ocular involvement (Konrad et al. 2006; Faguer et al. 2011). This inherited renal disorder is characterized by excessive urinary calcium and magnesium excretion, which progressively leads to chronic renal failure. Compared with renal hypomagnesemia 3 caused by CLDN16 mutations, the additional phenotype caused by CLDN19 mutations is severe visual impairment characterized by macular colobomata, significant myopia and horizontal nystagmus.
Genetics
Renal hypomagnesemia 5 is an autosomal recessive disorder caused by defects in the CLDN19 gene (Konrad et al. 2006; Godron et al. 2012). CLDN19 has 5 coding exons that encode the renal tight junction protein claudin 19. Causative genetic defects of CLDN19 throughout the whole coding region include missense/nonsense mutations and small deletion/insertions (Human Gene Mutation Database). Exon-level large deletions involving CLDN19 have also been reported, but are relatively uncommon (Godron et al. 2012).
Clinical Sensitivity - Sequencing with CNV PGxome
Mutation detection rate of the CLDN19 gene in a large cohort of patients with renal hypomagnesemia 5 is unavailable in the literature, however nearly all reported causative mutations are detectable by sequencing.
Testing Strategy
This test provides full coverage of all coding exons of the CLDN19 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
Candidates for this test are patients with renal hypomagnesemia 5. Testing is also indicated for family members of patients who have known CLDN19 mutations. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in CLDN19.
Candidates for this test are patients with renal hypomagnesemia 5. Testing is also indicated for family members of patients who have known CLDN19 mutations. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in CLDN19.
Gene
| Official Gene Symbol | OMIM ID |
|---|---|
| CLDN19 | 610036 |
| Inheritance | Abbreviation |
|---|---|
| Autosomal Dominant | AD |
| Autosomal Recessive | AR |
| X-Linked | XL |
| Mitochondrial | MT |
Disease
| Name | Inheritance | OMIM ID |
|---|---|---|
| Hypomagnesemia 5, Renal, With Ocular Involvement | AR | 248190 |
Related Tests
| Name |
|---|
| Hypomagnesemia Panel |
| Nephrolithiasis and Nephrocalcinosis Panel |
Citations
- Faguer S, Chauveau D, Cintas P, Tack I, Cointault O, Rostaing L, Vargas-Poussou R, Ribes D. 2011. Renal, ocular, and neuromuscular involvements in patients with CLDN19 mutations. Clin J Am Soc Nephrol 6: 355–360. PubMed ID: 21030577
- Godron A, Harambat J, Boccio V, Mensire A, May A, Rigothier C, Couzi L, Barrou B, Godin M, Chauveau D, Faguer S, Vallet M, et al. 2012. Familial hypomagnesemia with hypercalciuria and nephrocalcinosis: phenotype-genotype correlation and outcome in 32 patients with CLDN16 or CLDN19 mutations. Clin J Am Soc Nephrol 7: 801-809. PubMed ID: 22422540
- Human Gene Mutation Database (Bio-base).
- Konrad M, Schaller A, Seelow D, Pandey AV, Waldegger S, Lesslauer A, Vitzthum H, Suzuki Y, Luk JM, Becker C, Schlingmann KP, Schmid M, et al. 2006. Mutations in the tight-junction gene claudin 19 (CLDN19) are associated with renal magnesium wasting, renal failure, and severe ocular involvement. Am. J. Hum. Genet. 79: 949–957. PubMed ID: 17033971
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
Loading...
×
ORDER OPTIONS
View Ordering Instructions1) Select Test Type
2) Select Additional Test Options
No Additional Test Options are available for this test.