Can you get a colonospy at any age?

Reason for colonosco: Everybody should do screen for colon cancer starting at age 50. One way of screening is colonoscopy. If somebody has risk factor like 2 family members had colon cancer she should do colonoscopy 10 years earlier than the family member had colon cancer. Like if your father had cancer at age 45, you should do colonoscopy at 35. Familial polyposis needs screening at much earlier age.