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Genetic Analysis of Gray Platelet Syndrome

This study has been completed.
Information provided by (Responsible Party):
National Institutes of Health Clinical Center (CC) ( National Human Genome Research Institute (NHGRI) ) Identifier:
First received: September 29, 2003
Last updated: May 20, 2017
Last verified: May 10, 2017

This study will identify and characterize the gene or genes responsible for Gray Platelet syndrome (GPS). Platelets are small blood cells that stick on injured blood vessels to form a plug and stop bleeding. When a blood vessel is injured (like a cut on a finger), platelets release the proteins stored in their sacs to help form a blood clot. Patients with GPS bleed longer than other people because their platelets lack some of these protein-carrying sacs. Platelets without sacs look pale gray under the microscope rather than pink, giving the syndrome its name. Except for rare patients with severe hemorrhage, the bleeding tendency in GPS is usually mild to moderate, with patients experiencing easy bruising, nosebleeds, and, in women, excessive menstrual bleeding.

Patients with GPS and members of their family with GPS may be eligible for this study. Participants will provide a personal and family medical history and will have blood drawn. About 1 to 2 tablespoons of blood will be drawn in adults, and about 1 teaspoon in children. The blood will be analyzed for genes that cause GPS

Genetic Linkage

Study Type: Observational
Official Title: Genetic Analysis of Gray Platelet Syndrome

Resource links provided by NLM:

Further study details as provided by National Institutes of Health Clinical Center (CC):

Enrollment: 123
Study Start Date: September 25, 2003
Detailed Description:
Patients with Gray Platelet Syndrome (GPS) and their unaffected family members will be studied to identify the gene(s) involved in GPS using linkage analysis and gene mapping strategies. Up to 200 individual members of GPS families will be investigated to identify candidate regions of the human genome, which will be further studied using fine mapping and sequence analysis. Characterization of gene(s) involved in GPS could provide important insight into the mechanisms of vesicle formation and protein sorting in human cells.

Ages Eligible for Study:   1 Year to 80 Years   (Child, Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Enrollment in this study will be limited to patients diagnosed with GPS and their unaffected relatives. The diagnosis will be based upon absence or marked reduction of platelet Alpha-granules on electron microscopy.


Patients with reduction in both Alpha and Beta granules will be excluded, since this is probably a separate disease.

  Contacts and Locations
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Please refer to this study by its identifier: NCT00069680

United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
National Human Genome Research Institute (NHGRI)
Principal Investigator: Meral Gunay-Aygun, M.D. National Human Genome Research Institute (NHGRI)
  More Information

Additional Information:
Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: National Human Genome Research Institute (NHGRI) Identifier: NCT00069680     History of Changes
Other Study ID Numbers: 030313
Study First Received: September 29, 2003
Last Updated: May 20, 2017

Keywords provided by National Institutes of Health Clinical Center (CC):
Gene Identification
Linkage Analysis
Homozygosity Mapping
Gray Platelet Syndrome
Platelet Function Defect
Bleeding Disorder

Additional relevant MeSH terms:
Primary Myelofibrosis
Gray Platelet Syndrome
Myeloproliferative Disorders
Bone Marrow Diseases
Hematologic Diseases
Blood Platelet Disorders
Blood Coagulation Disorders, Inherited
Genetic Diseases, Inborn processed this record on May 24, 2017