DNA icon

Warburg Micro Syndrome Panel

Summary and Pricing

Test Method

Exome Sequencing with CNV Detection
Test Code Test Copy Genes Gene CPT Codes Copy CPT Codes
RAB18 81479,81479
RAB3GAP1 81479,81479
RAB3GAP2 81479,81479
TBC1D20 81479,81479
Test Code Test Copy Genes Panel CPT Code Gene CPT Codes Copy CPT Code Base Price
10185Genes x (4)81479 81479(x8) $990 Order Options and Pricing

Pricing Comments

We are happy to accommodate requests for testing single genes in this panel or a subset of these genes. The price will remain the list price. If desired, free reflex testing to remaining genes on panel is available. Alternatively, a single gene or subset of genes can also be ordered via our Custom Panel tool.

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).

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.


Genetic Counselors


  • Dana Talsness, PhD

Clinical Features and Genetics

Clinical Features

Warburg Micro syndrome (WMS) is a rare autosomal recessive disorder with brain, eye, and endocrine abnormalities. WMS is characterized by congenital microcephaly, cortical dysplasia, agenesis or hypoplasia of the corpus callosum, microphthalmia, microcornea, congenital cataracts, optic atrophy, profound intellectual disability, and hypogenitalism (Derbent et al. 2004; Graham et al. 2004; Handley et al. 2013).

WMS may be distinguished from other similar clinical disorders such as Cerebro-Oculo-Facio-Skeletal syndrome and Cockayne syndrome by normal nucleotide excision repair (NER) in cultured fibroblasts. It is also distinguished by the presence of significant visual abnormalities, frontal polymicrogyria, thin corpus callosum, and cortical atrophy by MRI. The most difficult differential diagnosis would be between WMS and Martsolf syndrome (MS). MS syndrome patients have a higher life expectancy, and MS is considered milder than WMS (Morris-Rosendahl et al. 2010).

WMS is a heterogeneous disorder; however, the gene involved cannot be ascertained based on clinical phenotype (Handley et al. 2013; Liegel et al. 2013).


WMS is an autosomal recessive disorder associated with causative variants in four genes: RAB3GAP1, RAB3GAP2, RAB18 and TBC1D20. MS has been associated with pathogenic variants in RAB3GAP2. Together, pathogenic variants in these genes account for about 50% of WMS and MS cases. Rabs are small G proteins of the Ras superfamily, which are involved in vesicular trafficking. RAB3GAP, which regulates Rab3 activity, is a heterodimeric complex consisting of a catalytic subunit encoded by RAB3GAP1 and a noncatalytic subunit encoded by RAB3GAP2. RAB18 encoded protein is mostly localized to lipid droplets and has a role in lipid dynamics and lipid storage activities. However, its relationship to RAB3GAP1 and RAB3GAP2 has not been investigated (Martin et al. 2005; Handley et al. 2013). Recently, TBC1D20, which is a RabGTPase-activating protein, has shown to be associated with WMS (Liegel et al. 2013).

So far ~50 pathogenic variants in RAB3GAP1 (truncating mutations, missense, splicing, small and gross deletions); ~10 pathogenic variants in RAB3GAP2 (truncating mutations, missense, splicing, small deletions and insertions), ~5 pathogenic variants in RAB18 (missense, nonsense, small and gross deletions) and ~5 pathogenic variants in TBC1D20 (nonsense, small and gross deletions) have been reported that are associated with WMS and MS (Human Gene Mutation Database).

See individual gene test descriptions for more information on molecular biology of gene products.

Clinical Sensitivity - Sequencing with CNV PGxome

In a study that investigated 153 families (144 WMS and 9 MS patients), pathogenic variants were identified in RAB3GAP1 (41% of cases), RAB3GAP2 (7% of cases), and RAB18 (5% of cases) (Handley et al. 2013). Sequence analysis of 77 families affected by WMS (negative for RAB3GAP1, RAB3GAP2, and RAB18 pathogenic variants), found seven individuals found to be homozygous for TBC1D20 pathogenic variants (Liegel et al. 2013).

Testing Strategy

This test is performed using Next-Gen sequencing with additional Sanger sequencing as necessary.

This panel provides 100% coverage of all coding exons of the genes 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 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

All patients with symptoms suggestive of Warburg Micro syndrome and Martsolf syndrome are candidates.


Official Gene Symbol OMIM ID
RAB18 602207
RAB3GAP1 602536
RAB3GAP2 609275
TBC1D20 611663
Inheritance Abbreviation
Autosomal Dominant AD
Autosomal Recessive AR
X-Linked XL
Mitochondrial MT

Related Test



  • Derbent M. et al. 2004. American Journal of Medical Genetics. Part A 128A: 2324. PubMed ID: 15216542
  • Graham JM. et al. 2004. American Journal of Medical Genetics. Part A 128A: 23545. PubMed ID: 15216543
  • Handley MT. et al. 2013. Human Mutation 34: 68696. PubMed ID: 23420520
  • Human Gene Mutation Database (Bio-base).
  • Liegel RP. et al. 2013. American Journal of Human Genetics. 93: 1001-14. PubMed ID: 24239381
  • Martin S. et al. 2005. The Journal of Biological Chemistry. 280: 42325-35. PubMed ID: 16207721
  • Morris-Rosendahl DJ. et al. 2010. European Journal of Human Genetics : Ejhg. 18: 1100-6. PubMed ID: 20512159


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 Loading... ×


An error has occurred while calculating the price. Please try again or contact us for assistance.

View Ordering Instructions

1) Select Test Method (Platform)

1) Select Test Type

2) Select Additional Test Options

No Additional Test Options are available for this test.

Note: acceptable specimen types are whole blood and DNA from whole blood only.
Total Price: loading
Patient Prompt Pay Price: loading
A patient prompt pay discount is available if payment is made by the patient and received prior to the time of reporting.
Show Patient Prompt Pay Price
Copy Text to Clipboard