University College London

Academic Institute

OFHS260084

Thrombotic thrombocytopenic purpura, or TTP, is a rare blood disease. In TTP, the body loses a protein that controls blood clotting. Tiny clots then block small blood vessels. This can harm the brain, kidneys and heart. Without quick treatment, most people with TTP would die. Many who survive live with lasting problems. These include tiredness, poor memory, low mood and high blood pressure. Most cases start when the immune system attacks this protein by mistake. This type is more common, and often more severe, in people of African descent. Almost all genetic studies of TTP so far have looked at people of European descent. We therefore know very little about risk in other groups. Our first aim is to find gene changes that raise the risk of this type of TTP in people of African descent. We will compare people who have the disease with Our Future Health volunteers of a similar genetic background. The gene for the protein affected in TTP varies in everyone else too. Our second aim is to test whether these changes alter the risk of common illnesses. These include stroke, heart attack and blood clots. Blood must clot to stop bleeding, but clots must not grow too large. A protein in the blood, called ADAMTS13, helps keep this balance. When the body loses this protein, tiny clots form in small blood vessels. This causes the rare disease TTP. In most people with TTP, the immune system makes antibodies that attack the protein. A person’s genes help decide who this happens to. Studies have found risk genes in the immune system. However, nearly all this work was done in people of European descent. We still do not know which genes matter the most in TTP patients in other groups. Small, common changes in the gene for ADAMTS13 are found in everyone. They alter how well the protein works. People with lower activity appear to have more strokes and heart attacks. Rarer changes are picked up by genetic tests, and doctors often cannot say what they mean. Our Future Health is very large and includes people of many backgrounds. It links genes to heath records. This makes it a strong resource for answering both questions in one study.

About six people in a million develop TTP each year. Treatment has improved, but the illness is still serious. Many people have further attacks. Many also live with tiredness, memory problems, high blood pressure and low mood. The UK TTP Registry, the largest registry of its kind, is run from University College London (UCL). We also work closely with TTP Network, a patient charity. Patients often ask us why they became ill. They also ask whether their children are at risk. This study will help us give better answers. Our results may help doctors find people at higher risk. They may help explain gene test results to families. In time, they may point to new treatments. The same gene affects clotting in everyone. So, our findings may help many more people than those living with TTP. They may add to what we know about stroke and heart disease. Black people are affected by TTP more often yet are often not included in genetic research. Our study will help to close that gap. This supports fairer care for all groups.

Public Health Research

28/08/2026

26/08/2026

TRE