Clinics and Departments

Laboratory Services

Lab Dept:

Anatomic Pathology

Test Name:

TGFBR1 &TGFBR2 GENE SEQUENCING

General Information

Lab Order Codes:

LDAB

Synonyms:

Loeys-Dietz syndrome, Type 1A (LDS1A) TGFBR1; Loeys-Dietz syndrome, Type 1B (LDS1B); Loeys-Dietz Types 1A/1B; LDS Types 1A/1B

CPT Codes:

81405 x2 – Molecular Pathology procedure, Level 6

Test Includes:

Direct DNA sequencing of PCR products generated from genomic DNA, sequencing of exons and exon-intron boundaries, point mutations, splice site mutations and small exonic deletions, insertions and indels.

Logistics

Test Indications:

For confirmation of symptoms and the clinical diagnosis related to Loeys-Dietz syndrome, type 1A (LDS1A) TGFBR1 and Loeys-Dietz syndrome, type 1B (LDS1B) TGFBR2.

Loeys-Dietz syndrome (LDS) is a recently described syndrome caused by mutations in one of two genes, TGFBR1 (Type 1A) or TGFBR2 (Type 1B). The reported phenotype is highly variable and overlaps considerably with Ehlers-Danlos syndrome IV or Marfan syndrome. A high percentage of patients have aortic root aneurysm or other arterial aneurysms. Some have cardiac abnormalities including patent ductus or atrial septal defects. Many display arterial tortuosity. Skeletal defects may include hypertelorism, pectus defects, joint laxity, craniosynostosis, arachnodactyly, scoliosis, talipes equinovarus, camptodactyly and malar hypoplasia. Some have dural ectasia. Additional features may include uterine, spleen or bowel rupture, thin, translucent, hyperextensible or velvety skin with atrophic scars and easy bruising. Blue sclera and a bifid uvula have also been observed.

Lab Testing Sections:

Anatomic Pathology - Sendouts

Referred to:

Connective Tissue Gene Tests (CTGT)

Phone Numbers:

MIN Lab: 612-813-6280

STP Lab: 651-220-6550

Test Availability:

Daily, 24 hours

Turnaround Time:

1 – 2 weeks

Special Instructions:

Please include a completed CTGT Request form with the patient or specimen to the laboratory.

Specimen

Specimen Type:

Whole blood

Container:

Lavender top (EDTA) tube

Draw Volume:

6 mL (Minimum: 4 mL) blood

Processed Volume:

Same as Draw Volume

Collection:

Routine venipuncture

Special Processing:

Lab Staff: Do Not centrifuge. Specimen should be sent in original collection container. Send via overnight shipping with a cold pack to reach CTGT Monday through Friday. If weekend or holiday when drawn, store at refrigerated temperatures. Please include a CTGT Shipment Packing Slip with the shipment.

Patient Preparation:

None

Sample Rejection:

Mislabled or unlabeled specimen

Interpretive

Reference Range:

Interpretive report

Critical Values:

N/A

Limitations:

Published estimates of test sensitivity for genes linked to certain disorders can be very inaccurate, and that it is difficult to predict the probability of detecting a mutation in any single gene for one individual. The following factors contribute to this challenge: Many disorders have overlapping phenotypes; some disorders are linked to mutations in more than one gene; in some instances genes remain to be linked to specific disorders; for most disorders, proper diagnosis requires that clinical findings are considered along with genetic findings.

Methodology:

DNA sequencing

References:

Connective Tissue Gene Tests June 2011
(484) 224-2900 Fax (484) 244-2904

Updates:

2/11/2013: CPT update
7/9/2013: CPT update CTGT, previously listed as 81406



  Lab Test Directory
    Chemistry
    Coagulation
    Flow/Immunology
    Hematology
    Microbiology/ Virology
    Other Fluids
    Pathology
    Serology
    Transfusion Services
    Urine/Stool

  Search Lab Test Directory
    List All Documents

  Lab Staff

  E-mail Lab Services