B. What is the purpose of this research study?

The purpose of this study is to better understand the cause of PHACE syndrome and similar diseases with large hemangiomas associated with other anomalies. This study hopes to find information that will help doctors understand the inheritance of genetic disorders and the changes in the body's cells and proteins that happen when someone has an inherited disease. If these genes and proteins can be better understood, then diagnosis and treatment may be improved. A specific type of gene mutation called "mosaic mutation" is suspected to be one of the causes of PHACE syndrome; this means the gene change is only in some cells in the body. To study whether that is true, we will ask to take a skin sample from your hemangioma if possible.

About 300 local children and adults with PHACE syndrome or large hemangiomas as well as their relatives will take part in this study. About 600 participants will be enrolled across the nation, and about 100 will be enrolled internationally. The total number of subjects and parents enrolled in the study will be about 1000.