This Core will be responsible for identifying all the participants in the studies of the Center. This core will identify potential participants, contact them for participation, and enroll them in the study. The core will help arrange appointments either in the clinics or in the home. They will also enroll parents. The Core will also perform numerous assessments on each of the participants, and draw blood samples for DNA extraction. There will be substantial coordination between the Duke and Vanderbilt arms of the Core. In addition, this Core will provide the bioinformatics support to database all the relevant clinical, medical history, family history, and genotypic information collected as part of the Center. The PEDIGENE@ system, already in place at both the DUMC and VUMC sites, will be used as the primary database system. PEDIGENE@ is already being used for numerous other projects and has been field tested for over 10 years.