Rare Blood Disorder Gene Found

Grey Platelet Syndrome identified by gene NBEAL2 with DNA test

(RxWiki News) Some diseases are so rare that even figuring out how to diagnose them can be tricky. The discovery of a gene for an extremely rare blood disorder could help make it easier to diagnose through DNA testing.

Researchers have found the gene that causes Grey Platelet Syndrome, a disease in which there are only 50 known cases. The finding could bode well for better identifying it in the future.

"If you bruise easily and have abnormal bleeding, see a doctor."

Willem Ouwehand, study co-author, and a professor who heads a NHS Blood and Transplant research team on platelet biology at both the Wellcome Trust Sanger Institute and the University of Cambridge, said that it is exciting to see modern genomics directly benefiting patient care. The finding could allow doctors to easily identify the rare disease, and gives researchers confidence that the same results can be achieved for many other rare inherited platelet bleeding disorders.

Some individuals are born with platelets that do not function well, a condition suspected to be inherited. Platelets, the second most abundant blood cell, orchestrate blood vessel wall repairs when it is needed. However, they also can cause blood clots that lead to heart attacks or strokes. Grey Platelet Syndrome is caused by the lack of an important protein in the platelets.

Those with Grey Platelet Syndrome are at risk for life-threatening bleeding, especially it if occurs in the brain. It was named for the grayish appearance of platelets when viewed with a microscope. Investigators have been working to pinpoint the gene responsible for 30 years.

An important step in genetic research has been using it to develop easier and faster DNA diagnostic tests. Genes must first be identified before this can occur. Previously, analyzing a person's genetics was the only way to identify rare disorders such as Grey Platelet Syndrome.

Researchers identified NBEAL2 as a gene that did not function well in patients with Grey Platelet Syndrome. In reviewing four unrelated patients, they found that patients affected by the disorder had inherited two non-functioning copies of the gene, one from their mother and another from their father.

Identification of the gene was confirmed by additional studies in zebra fish. Switching off the NBEAL2 gene in the fish resulted in about half of the fish suffering spontaneous bleeding, much like patients with the disorder.

Review Date: 
July 27, 2011