Test ID: PRSNG    
Protein S Deficiency, PROS1 Gene, Next-Generation Sequencing, Varies

Ascertaining a pathogenic alteration in the PROS1 gene of patient with congenital protein S deficiency

This test is not intended for prenatal diagnosis

This test detects pathogenic alterations in the PROS1 gene to delineate the underlying molecular defect in a patient with a laboratory diagnosis of thrombophilia due to protein S deficiency.

The gene target for this test is:

Gene name (transcript): PROS1 (GRCh37 [hg19] NM_000313)

Chromosomal location: 3q11.1

At Mayo Clinic, measurement of plasma free protein S antigen (PSTF / Protein S Antigen, Plasma) is performed as the initial testing for protein S deficiency. If the free protein S antigen is abnormal, then the total plasma protein S antigen will be performed to distinguish between types I and III protein S deficiency. For patients in whom hereditary protein S deficiency is strongly suspected and the free plasma protein S antigen level is normal, consideration should be given to testing of free protein S activity, S_FX / Protein S Activity, Plasma, for detecting type II protein S deficiency.

Genetic testing for protein S deficiency is indicated if:

- Free protein S antigen and/or activity is abnormally reduced

- Preanalytical variables and acquired causes of protein S deficiency have been excluded (eg, acute thrombosis, surgery, disseminated intravascular coagulation [DIC], liver disease, vitamin K deficiency, therapy with vitamin K antagonists such as warfarin, pregnancy, treatment with hormonal contraceptives, HIV infection, varicella, sickle cell disease, malignancy, nephrotic syndrome)

• 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.