Each column keeps its native condition scope. Initial features are displayed alphabetically, not ranked by clinical importance. Counts remain separate, and an empty cell does not mean a feature cannot occur.
"},"coverage":{"countRecords":0,"emptyColumnKeys":[],"hpoRelease":"2026-06-23","narrativeSourceChanges":[],"records":8,"sourceGroups":{"omim":8,"orphanet":0,"published":0}},"features":[{"hpoId":"HP:0004420","label":"Arterial thrombosis","primary":false},{"hpoId":"HP:0005305","label":"Cerebral venous thrombosis","primary":false},{"hpoId":"HP:0100724","label":"Hypercoagulability","primary":false},{"hpoId":"HP:0002204","label":"Pulmonary embolism","primary":false},{"hpoId":"HP:0000979","label":"Purpura","primary":false},{"hpoId":"HP:0004855","label":"Reduced protein S activity","primary":false},{"hpoId":"HP:0002638","label":"Superficial thrombophlebitis","primary":false},{"hpoId":"HP:0001038","label":"Warfarin-induced skin necrosis","primary":false}],"ledeHtml":"Protein S deficiency is a disorder that increases the risk of developing blood clots. People with protein S deficiency are at risk of developing a type of clot called a deep vein thrombosis (DVT) that occurs in the deep veins of the arms or legs. A DVT can travel through the bloodstream and lodge in the lungs, causing a life-threatening clot called a pulmonary embolism (PE). Both DVTs and PEs are a type of venous thromboembolism, a general term for blood clots that form in a vein. Factors such as age, surgery, immobility, or pregnancy can increase the risk of clotting in people with protein S deficiency. In addition, people who have protein S deficiency and another inherited blood clotting disorder may have a higher risk of developing blood clots. Venous thromboembolism occurs in approximately fifty to sixty percent of people with protein S deficiency.","mondoId":"MONDO:0012868","records":[{"frequencyKind":"reported","key":"14f3acc4632ab114fbf87ff85641ec257c681bc7a0103c9c361010647b3502d8","raw":{"aspect":"P","body_system":"blood","disease_id":"OMIM:612336","disease_name":"Thrombophilia, hereditary, due to protein S deficiency, autosomal","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0100724","is_excluded":false,"label":"Hypercoagulability","onset_id":null,"reference":"OMIM:612336","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"71f56b92163ee6240e6d3ec9d32fb8199f3f3b3b9235a03a484de7136a96bee6","raw":{"aspect":"P","body_system":"blood","disease_id":"OMIM:612336","disease_name":"Thrombophilia, hereditary, due to protein S deficiency, autosomal","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0002638","is_excluded":false,"label":"Superficial thrombophlebitis","onset_id":null,"reference":"OMIM:612336","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"89ad34187e2ef4389e76816eca8d40ee09437c666afd127c1862180064eab530","raw":{"aspect":"P","body_system":"blood","disease_id":"OMIM:612336","disease_name":"Thrombophilia, hereditary, due to protein S deficiency, autosomal","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0004420","is_excluded":false,"label":"Arterial thrombosis","onset_id":null,"reference":"OMIM:612336","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"9e25a6bd495da2b57a5c7b07416cbc99b8ba9fc249dd6dcaa000ab8a1f6e018f","raw":{"aspect":"P","body_system":"skin","disease_id":"OMIM:612336","disease_name":"Thrombophilia, hereditary, due to protein S deficiency, autosomal","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0001038","is_excluded":false,"label":"Warfarin-induced skin necrosis","onset_id":null,"reference":"OMIM:612336","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"9f2c1ec224927a9206492af3d128a70ce1acf12fc806c3004271dab977160a27","raw":{"aspect":"P","body_system":"blood","disease_id":"OMIM:612336","disease_name":"Thrombophilia, hereditary, due to protein S deficiency, autosomal","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0000979","is_excluded":false,"label":"Purpura","onset_id":null,"reference":"OMIM:612336","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"a0da6e6d0b366d9bff75f9f846fe276773351b687e75c86d448b1027aa573c89","raw":{"aspect":"P","body_system":"respiratory","disease_id":"OMIM:612336","disease_name":"Thrombophilia, hereditary, due to protein S deficiency, autosomal","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0002204","is_excluded":false,"label":"Pulmonary embolism","onset_id":null,"reference":"OMIM:612336","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"bef1af0a959b2f915a637bed261b8f4849f7fcb8ad0e7e720b94102cf00c19a7","raw":{"aspect":"P","body_system":"blood","disease_id":"OMIM:612336","disease_name":"Thrombophilia, hereditary, due to protein S deficiency, autosomal","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0004855","is_excluded":false,"label":"Reduced protein S activity","onset_id":null,"reference":"OMIM:612336","source_release":"2026-06-23"},"sourceGroups":["omim"]},{"frequencyKind":"reported","key":"e5ad8a7f41473993eba28e7c29eb27b39bd90461367a787b02dc3c74799d8f62","raw":{"aspect":"P","body_system":"blood","disease_id":"OMIM:612336","disease_name":"Thrombophilia, hereditary, due to protein S deficiency, autosomal","evidence":"IEA","frequency_raw":null,"hpo_id":"HP:0005305","is_excluded":false,"label":"Cerebral venous thrombosis","onset_id":null,"reference":"OMIM:612336","source_release":"2026-06-23"},"sourceGroups":["omim"]}],"referenceLabels":{},"references":{"causeHtml":"","identityNote":"MONDO cross-references identify native condition entries. Ancestor membership does not transfer phenotype values between groups.","importantHtml":""},"sections":[{"bodyHtml":"Protein S deficiency can be caused by variants (also called mutations) in the PROS1 gene. This gene provides instructions for making protein S, which is found in the bloodstream and is important for the control of blood clotting. Protein S helps block the activity of (inactivate) certain proteins that promote the formation of blood clots.
Most variants that cause protein S deficiency change single DNA building blocks (base pairs) in the PROS1 gene. These gene variants change the amount of functional protein S. Individuals with protein S deficiency may not have enough functional protein S to inactivate clotting proteins, which increases the risk of developing blood clots.
Some cases of protein S deficiency are acquired, which means they do not appear to be caused by gene variants. Causes of acquired protein S deficiency include vitamin K deficiency, liver disease, and kidney disorders.
","key":"forms","title":"What causes Protein S deficiency?"},{"bodyHtml":"In rare cases, individuals have a severe form of protein S deficiency with signs and symptoms that develop soon after birth. Affected infants typically develop a life-threatening blood clotting disorder called purpura fulminans. Purpura fulminans is characterized by the formation of blood clots within small blood vessels throughout the body. These blood clots disrupt normal blood flow and can lead to the death of tissues (necrosis). Widespread blood clotting uses up all available blood clotting proteins. As a result, the body can no longer create clots, and bleeding occurs in various parts of the body. This abnormal bleeding often appears as large, purple skin lesions. Affected individuals who survive the newborn period may experience recurrent episodes of purpura fulminans.
Source: MedlinePlus Genetics
","key":"overview","title":"Condition overview"}],"sharedSources":[],"slug":"protein-s-deficiency","sourceDocuments":[{"name":"Protein S deficiency","reviewed":"2024-04","sections":{"causes":{"fetchedAt":"2026-10-20T20:24:30.142973+00:00","label":"Causes","pageSha256":"d0082f2c98e96d9a96a83fdf280fd0ff5a137e6db0edd48d38d08f0399e16f8e","sourceUrl":"https://medlineplus.gov/genetics/condition/protein-s-deficiency/#causes","status":"available"}},"source_release":"2026-10-01","url":"https://medlineplus.gov/genetics/condition/protein-s-deficiency"}],"sourceNote":"MedlinePlus descriptions and Causes; original HPO annotations.","takeawayHtml":"Cause explanations are from MedlinePlus Genetics. Feature values below retain their original sources and patient groups.","title":"Protein S deficiency"},"schemaVersion":1}