This is "novel," Hayward said, "as QPD is the very first bleeding disorder attributed to having an extra copy of a gene, rather than a defective copy. QPD is also the first bleeding problem attributed to a mutation in the uPA gene."
"The types of mutation that causes some bleeding problems are mistakes that are likely to happen again, and typically, they cause a protein to become defective or deficient," said Hayward. "Now that we know the mutation, we can focus on solving why there is tremendous uPA overproduction in QPD platelets, which will give us fundamental, new insights on how the uPA gene is controlled."
The work is already having a positive impact on the lives of many people. A recent newborn of the family most impacted by the condition was able to have a test immediately to discover whether he had the condition.
"The family needed to know whether this child would need life-long monitoring, and treatments to counteract their clot busting platelets, as having a definite yes or no answer early is key to proper treatment," said Hayward.
Hayward's group at McMaster worked with a Canadian team of investigators including Andrew Paterson at the Hospital for Sick Children in Toronto, and Georges Rivard at the University of Montreal.
Hayward and Rivard believe that the known cases they have studied over the last decade are "the tip of the iceberg" and that the true prevalence of QPD has been underestimated because, until the genetic test became available, there was no way to routinely test bleeders for this condition.
"Diagnosis is important as drugs for other platelet problems and transfusions just don't work for the QPD clot busting problem," said Hayward.
|Contact: Laura Thompson|