Rare Hematology News

Disease Profile

Gray platelet syndrome

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

<1 / 1 000 000

US Estimated

Europe Estimated

Age of onset






Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

GPS; Platelet alpha-granule deficiency; Marked decrease or absence of alpha-granules and of platelet-specific alpha-granule proteins


Blood Diseases; Congenital and Genetic Diseases


Gray platelet syndrome (GPS) is a rare inherited bleeding disorder characterized by platelets that have a gray appearance, severe thrombocytopenia, myelofibrosis, and splenomegaly. About 60 cases from various populations around the world have been described in the literature to date. GPS results from the absence or reduction of alpha-granules in platelets, which store proteins that promote platelet adhesiveness and wound healing when secreted during an injury. GPS is caused by mutations in the NBEAL2 gene and inherited in an autosomal recessive manner.[1][2]


Signs and symptoms usually appear at birth or in early childhood and include low platelet counts, easy bruising, prolonged bleeding, and nose bleeds. Affected individuals often have myelofibrosis and splenomegaly. Bleeding tendency is usually mild to moderate in those with mild thrombocytopenia. However, the thrombocytopenia and myelofibrosis are usually progressive in nature. GPS may result in fatal hemorrhage (bleeding), especially in adulthood when platelet counts are further decreased. Female patients may develop heavy menstrual bleeding.[1]

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
80%-99% of people have these symptoms
Bruising susceptibility
Bruise easily
Easy bruisability
Easy bruising

[ more ]

Low platelet count
30%-79% of people have these symptoms
Abnormality of the menstrual cycle
Bloody nose
Frequent nosebleeds
Nose bleed
Nose bleeding

[ more ]

Increased spleen size
Percent of people who have these symptoms is not available through HPO
Abnormal number of alpha granules
Autosomal recessive inheritance
Impaired collagen-induced platelet aggregation
Impaired thrombin-induced platelet aggregation
Abnormally heavy bleeding during menstruation
Worsens with time
Prolonged bleeding time
Reduced quantity of Von Willebrand factor
Reduced von Willebrand factor activity


Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.


    There is no specific treatment for GPS, but management involves anticipating and preventing risks of bleeding (e.g. possible platelet transfusions before surgery). Treatment may also include administration of desmopressin. Splenectomy should be considered to increase the platelet counts in those whose platelet counts decrease to approximately 30,000/microliter. Prognosis is generally good early in life when thrombocytopenia is mild. Those with platelets counts less than 30,000/microliter are at risk for life-threatening bleeding.[1]


    Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

    Organizations Supporting this Disease

      Learn more

      These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

      Where to Start

        In-Depth Information

        • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
        • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
        • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
        • PubMed is a searchable database of medical literature and lists journal articles that discuss Gray platelet syndrome. Click on the link to view a sample search on this topic.


          1. Gunay-Aygun M & Gahl WA. Gray platelet syndrome. Orphanet. June 2011; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=721. Accessed 10/3/2011.
          2. Gray Platelet Syndrome, GPS. Online Mendelian Inheritance of Man (OMIM). August 2011; https://omim.org/entry/139090. Accessed 10/3/2011.

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