Test ID: F2NGS    
F2 Gene, Next-Generation Sequencing, Varies

Ascertaining a causative alteration in F2 and the affected region of prothrombin protein in an individual clinically diagnosed with factor II deficiency

Carrier testing for close family members of an individual with a factor II deficiency diagnosis

This test is not intended for prenatal diagnosis.

This test detects pathogenic alterations in the F2 gene to delineate the underlying molecular defect in a patient with a laboratory diagnosis of factor II (prothrombin) deficiency (F2D).

The gene target for this test is:

Gene name (transcript): F2 (GRCh37 [hg19] NM_000506)

Chromosomal location: 11p11.2

The clinical workup for factor II deficiency (F2D) begins with special coagulation testing for factor II. See  F_2 / Coagulation Factor II Activity Assay, Plasma.

Genetic testing for F2D is indicated if:

-Prothrombin (factor II) activity is reduced (less than 80% of normal)

-Acquired causes of factor II deficiency have been excluded (eg, vitamin K deficiency, warfarin anticoagulation use, liver disease, etc)

Prothrombin antigen testing, to distinguish between type I and type II deficiencies, may be helpful in cases where genetic testing results yield variants of uncertain significance.

• Informed Consent for Genetic Testing
• Informed Consent for Genetic Testing (Spanish)
• Rare Coagulation Disorder Patient Information

Custom Sequence Capture and Targeted Next-Generation Sequencing (NGS) followed by Polymerase Chain Reaction (PCR) and Sanger Sequencing when appropriate