Resistance to Thyroid Hormone (RTH) Gene Sequencing

Test Code

16053

CPT Codes
81405

Includes

If amniotic fluid or chorionic villi sampling (CVS) is received, then an additional charge will be added for cell culture work (CPT code(s): 88235) if not already ordered

Preferred Specimen

5 mL whole blood collected in an EDTA (lavender-top), ACD (yellow-top) or sodium heparin (green-top) tube

Minimum Volume

3 mL whole blood • 10 mL amniotic fluid • 10 mg chorionic villi

Other Acceptable Specimens

10 mL amniotic fluid • 10 mg chorionic villi collected in a sterile, leak-proof container • Cultured cells (75% confluent minimum) collected in each of two sterile T-25 flasks

Instructions

Do not hold specimen; forward to laboratory when specimen arrives. Contact performing laboratory for stability determination. For any other sample type call 866-GENE-INFO (1-866-436-3463).

Whole blood: Normal phlebotomy procedure. Specimen stability is crucial. Store and ship room temperature immediately. Do not freeze.

For fetal testing:
1) Please call 1-866-GENE-INFO (1-866-436-3463) prior to submission.
2) Documentation of parental carrier status must be provided.
3) It is required that Maternal Cell Contamination Study, STR Analysis be ordered in conjunction with fetal testing. A separate tube of maternal blood (EDTA) is required for this test.

Amniotic fluid: Normal collection procedure. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; forward to laboratory when sample arrives.

Amniocyte or Chorionic Villus (CVS) culture: Two sterile T25 flasks, 75% confluent, filled with culture medium. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; forward to laboratory when cells arrive.

Dissected Chorionic Villus (CVS) biopsy: 10-20 mg dissected chorionic villi collected in a sterile tube, filled with sterile culture medium. Specimen stability is crucial. Store and ship at room temperature immediately. Do not refrigerate or freeze; forward to laboratory when sample arrives.

Transport Temperature

Room temperature

Specimen Stability

Whole blood
Room temperature: 14 days
Refrigerated: 14 days
Frozen: Unacceptable

Fetal specimens
Room temperature: 48 hours
Refrigerated: Unacceptable
Frozen: Unacceptable

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Do not reject. Forward to performing laboratory for evaluation of sample.

Methodology
Next Generation Sequencing

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: As needed; Minimum 1x/week; Report available: 3-5 weeks

Reference Range

Negative

Clinical Significance

This test detects variants in the THRB gene associated with Resistance to Thyroid Hormone (RTH). It can be used to confirm a diagnosis of RTH in affected individuals and identify familial variants.

Performing Laboratory

Quest Diagnostics Nichols Institute-San Juan Capistrano, CA

33608 Ortega Highway

San Juan Capistrano, CA 92675-2042

Last Updated: May 19, 2016

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.