Hereditary Haemorrhagic Telangiectasia (HHT, also known as Osler-Weber-Rendu Syndrome) is an disease that leads to the development of dilated and fragile blood vessels. We propose to obtain small skin samples from patients with HHT in order to analyze the samples using histological methods, and study the properties of vascular endothelial cells derived from patients. We hypothesize that these cells will show altered growth, migration, and protein synthetic differences when compared to normal endothelial cells, which may be confirmed in single time point analyses in histological samples. We anticipate that that these findings may help to explain aspects of the HHT disease phenotype.