Test ID: FBN1B    
FBN1 Full Gene Sequence, Varies

In cases where there are hallmark features of Marfan syndrome, in particular the combination of ectopia lentis and aortic aneurysm or dissection in a patient or their family, FBN1 analysis (this assay) may be an appropriate first step in testing. In cases with more nonspecific features, such as isolated ascending aortic aneurysm or isolated skeletal features of Marfan syndrome, MFRGP / Marfan Syndrome and Related Disorders Multi-Gene Panel, Varies may be the more appropriate test to choose. Professional clinical judgment should be used by the ordering clinician. A genetic consultation may be helpful in determining the appropriate testing strategy for your patient.

Targeted testing for familial variants (also called site-specific or known mutations testing) is available for this gene. See FMTT / Familial Mutation, Targeted Testing, Varies.

Specimen preferred to arrive within 96 hours of collection.

1. Marfan and Related Disorders Patient Information (T636) is required, see Special Instructions. Testing may proceed without the patient information however it aids in providing a more thorough interpretation. Ordering providers are strongly encouraged to complete the form and send it with the specimen.

2. Include physician name and phone number with specimen.

Prior Authorization is available for this test. Submit the required form with the specimen.

Submit only 1 of the following specimens:

Specimen Type: Whole blood

Container/Tube: Lavender top (EDTA)

Specimen Volume: 3 mL

Collection Instructions:

1. Invert several times to mix blood.

2. Send specimen in original tube.

Specimen Stability Information: Ambient (preferred) 4 days/Refrigerated 14 days

Specimen Type: DNA

Container/Tube: 2 mL screw top tube

Specimen Volume: 100 mcL (microliters)

Collection Instructions:

1. The preferred volume is 100 mcL at a concentration of 250 ng/mcL.

2. Include concentration and volume on tube.

Specimen Stability Information: Frozen (preferred)/Ambient/Refrigerated

• Informed Consent for Genetic Testing
• Marfan and Related Disorders Patient Information
• FBN1, Full Gene Sequence Prior Authorization Ordering Instructions
• Informed Consent for Genetic Testing (Spanish)

1. New York Clients-Informed consent is required. Document on the request form or electronic order that a copy is on file. The following documents are available in Special Instructions:

-Informed Consent for Genetic Testing (T576)

-Informed Consent for Genetic Testing-Spanish (T826)

2. FBN1, Full Gene Sequence Prior Authorization Ordering Instructions in Special Instructions.

3. If not ordering electronically, complete, print, and send a Cardiovascular Test Request Form (T724) with the specimen.