Overview
Gray platelet syndrome (GPS), also known as alpha-granule deficiency, is a rare inherited blood disorder that affects tiny blood cells called platelets. Platelets are responsible for helping your blood clot when you get a cut or injury. In GPS, platelets are missing special storage compartments called alpha-granules, which normally hold proteins that help with clotting and healing. Without these granules, the platelets appear pale gray under a microscope — which is how the disease got its name. People with GPS typically experience easy bruising, prolonged bleeding from cuts, heavy menstrual periods, and nosebleeds that are hard to stop. The bleeding is usually mild to moderate, though it can become serious during surgery or after an injury. Over time, many people with GPS also develop a condition called myelofibrosis, where scar tissue builds up in the bone marrow, and an enlarged spleen. Some people also develop a type of immune-related kidney disease. There is currently no cure for GPS. Treatment focuses on managing bleeding episodes and may include platelet transfusions before surgery, medications to reduce bleeding risk, and regular monitoring of blood counts and bone marrow health. Most people with GPS can live relatively normal lives with careful medical management, though the condition requires lifelong attention.
Key symptoms:
Easy bruisingProlonged bleeding from cuts or woundsFrequent or hard-to-stop nosebleedsHeavy or prolonged menstrual periodsBleeding gumsEnlarged spleen (splenomegaly)Low platelet count (thrombocytopenia)Fatigue related to anemiaScarring of the bone marrow (myelofibrosis) over timeIncreased risk of bleeding during surgery or dental proceduresOccasional blood in urine or stool in severe casesImmune-related kidney inflammation (in some patients)
Clinical phenotype terms (8)— hover any for plain English
Autosomal recessive
Passed on when both parents carry the same gene change; often skips generations
Variable
Can begin at different ages, from infancy through adulthood
FDA & Trial Timeline
10 eventsVirginia Commonwealth University — NA
University of Maia
Spine Centre of Southern Denmark — NA
University of Kentucky — NA
Iberoamerican Institute of Sports Science and Human Movement
Northwestern University
CHU de Quebec-Universite Laval — NA
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Gray platelet syndrome.
View clinical trials →Clinical Trials
View all trials with filters →No actively recruiting trials found for Gray platelet syndrome at this time.
New trials open frequently. Follow this disease to get notified.
Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Gray platelet syndrome.
Community
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Start the conversation →Latest news about Gray platelet syndrome
Disease timeline:
New recruiting trial: TRAC-ER Intervention to Reduce Risky Alcohol Use and HIV Risk
A new clinical trial is recruiting patients for Gray platelet syndrome
New recruiting trial: Assessing Ambulatory and Non-ambulatory Community Mobility in People With Lower Limb Amputation
A new clinical trial is recruiting patients for Gray platelet syndrome
New recruiting trial: GPS Project Evaluation of the Impact of the Reorganization of Work Into a Family Medicine Group on Pharmacotherapy and Support for the Autonomy of Seniors With Major Neurocognitive Disorders
A new clinical trial is recruiting patients for Gray platelet syndrome
New recruiting trial: MRI And GPS Informing Choices for Prostate Cancer Treatment (MAGIC)
A new clinical trial is recruiting patients for Gray platelet syndrome
New recruiting trial: Global Paradise System US Post Approval Study
A new clinical trial is recruiting patients for Gray platelet syndrome
New recruiting trial: Comparison Between Exactech Guided Personalized Surgery (GPS) and Conventional Instrumentation of Shoulder Arthroplasty
A new clinical trial is recruiting patients for Gray platelet syndrome
New recruiting trial: Hepatitis C Tracker Study
A new clinical trial is recruiting patients for Gray platelet syndrome
New recruiting trial: Continuous Mobility and Physical Activity in Vertebroplasty vs Sham for Osteoporotic Vertebral Fracture
A new clinical trial is recruiting patients for Gray platelet syndrome
New recruiting trial: Geolocation Positional System (GPS) Experience
A new clinical trial is recruiting patients for Gray platelet syndrome
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.What level of bleeding risk do I have, and what activities should I avoid?,How often should I have my blood counts and bone marrow checked?,What should I do — and who should I call — if I have uncontrolled bleeding at home?,Do I need to take any special precautions before dental work or surgery?,Should my family members be tested for this condition?,Are there any clinical trials or new treatments I should know about?,What medications are safe for me to take for pain or fever, and which ones should I avoid?
Common questions about Gray platelet syndrome
What is Gray platelet syndrome?
Gray platelet syndrome (GPS), also known as alpha-granule deficiency, is a rare inherited blood disorder that affects tiny blood cells called platelets. Platelets are responsible for helping your blood clot when you get a cut or injury. In GPS, platelets are missing special storage compartments called alpha-granules, which normally hold proteins that help with clotting and healing. Without these granules, the platelets appear pale gray under a microscope — which is how the disease got its name. People with GPS typically experience easy bruising, prolonged bleeding from cuts, heavy menstrual p
How is Gray platelet syndrome inherited?
Gray platelet syndrome follows a autosomal recessive inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
Which specialists treat Gray platelet syndrome?
2 specialists and care centers treating Gray platelet syndrome are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.