DNA icon

Cutis Laxa via the LTBP4 Gene

Summary and Pricing

Test Method

Exome Sequencing with CNV Detection
Test Code Test Copy GenesTest CPT Code Gene CPT Codes Copy CPT Codes Base Price
LTBP4 81479 81479,81479 $990
Test Code Test Copy Genes Test CPT Code Gene CPT Codes Copy CPT Code Base Price
8015LTBP481479 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.


Genetic Counselors


  • Stela Berisha, PhD, FACMG

Clinical Features and Genetics

Clinical Features

LTBP4-related Cutis laxa is characterized by skin laxity, bronchopulmonary dysplasia, gastrointestinal/urinary malformations, pulmonary artery stenosis, dysmorphic facial features, joint laxity and postnatal growth delay. Dysmorphic facial features include hypertelorism, microretrognathia, long philtrum and wide fontanelles (Urban et al. 2009).


Pathogenic variants in the LTBP4 gene cause autosomal recessive cutis laxa type IC. LTBP4 protein stands for latent transforming growth factor betas (TGFbs) binding protein 4, which modulates the activity of TGFbs (Oklü and Hesketh 2000). To date, more than 10 unique pathogenic LTBP4 pathogenic variants have been reported. They are: missense (19%), nonsense (38%), truncating (38%), and splicing (5%) (Callewaert et al. 2013; Human Gene Mutation Database). No large deletions or duplications have been reported.

Clinical Sensitivity - Sequencing with CNV PGxome

In one study, LTBP4 pathogenic variants were identified in 9 out of 12 studied families with cutis laxa (Callewaert B et al. 2013). Mutation detection rate should be high because all reported LTBP4 pathogenic variants are missense or nonsense/truncating pathogenic variants which can be detected by sequence analysis.

Testing Strategy

This test provides full coverage of all coding exons of the LTBP4 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 symptoms consistent with cuties laxa with pulmonary emphysema, pulmonary artery stenosis, gastrointestinal/urinary malformations, dysmorphic facial features and the family members of patients who have LTBP4 pathogenic variants. This test may also be considered for the reproductive partners of individuals who carry pathogenic variants in LTBP4.


Official Gene Symbol OMIM ID
LTBP4 604710
Inheritance Abbreviation
Autosomal Dominant AD
Autosomal Recessive AR
X-Linked XL
Mitochondrial MT

Related Tests

Autosomal Recessive Cutis Laxa Type 3A (ARCL3A) via the ALDH18A1 Gene
Autosomal Recessive Cutis Laxa Type IIA (ARCL2A) and Wrinkly Skin Syndrome (WSS) via the ATP6V0A2 Gene
Cutis Laxa via the FBLN5 Gene
Cutis Laxa via the PYCR1 Gene
Cutis Laxa, Type 1B (ARCL1B) via the EFEMP2 Gene
Macrocephaly, Alopecia, Cutis Laxa and Scoliosis (MACS) Syndrome via the RIN2 Gene


  • Callewaert B. et al. 2013. Human Mutation. 34: 111-21. PubMed ID: 22829427
  • Human Gene Mutation Database (Bio-base).
  • Oklü R., Hesketh R. 2000. The Biochemical Journal. 352 Pt 3: 601-10. PubMed ID: 11104663
  • Urban Z. et al. 2009. American Journal of Human Genetics. 85: 593-605. PubMed ID: 19836010


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