Specific Aim 2: To prospectively identify and recruit selected relatives (parents, grandparents, and same generation relatives - cousins and siblings) from the 45 probands identified in Specific Aim 1. In addition, for siblings and cousins of probands (i.e. relatives in the same generation as the proband), the investigators will obtain risk factor and food frequency questionnaires, and for colorectal cancer cases, tumor blocks and pathology reports of their cancers.