HDL, or good cholesterol, has been shown to protect against heart attack and stroke. How HDL works as a protective agent is not well understood. There is a family that has 4 generations of living members with high HDL level. In the study, after consent is obtained, we will obtain 2 tablespoons of blood from all the family members in order to study their cholesterol levels and to obtain DNA in order to determine if there is a pattern of inheritance for this trait. We will also have them fill out a questionnaire about their medical history, diet and activity level as all of these can affect their HDL levels. In addition we will obtain additional blood (about 2 tablespoons) for plasma, white blood cells and also perform a biopsy to obtain skin cells from a matched pair of family members with and without the trait in order to determine which genes might be turned on and off because of this trait. We also wish to study other families who have members with high HDL cholesterol as well. These individuals will be identified from a core database.
