Specific Aim 1: To prospectively identify and recruit approximately 300 CRC probands from two distinct geographical areas in PR (Metropolitan and Southern Region). From each proband the investigators will obtain a pedigree extended to second-degree relatives and cousins. Assuming 10% will be positive for a family history of CRC, the investigators will then recruit all 30 probands with a family history of CRC and a sample of 15 family-history negative probands and obtain: paraffin-embedded tumors blocks, blood samples, risk factor and food frequency questionnaires.