Bad Genes, But Which Ones?

A young woman with a history of a desmoid tumor as a child undergoes a screening colonoscopy. What gene mutation is suggested by the finding of multiple adenomatous polyps?

A 25-year-old woman undergoes a screening colonoscopy, recommended because of a family history of colon cancer. She is noted to have multiple polyps throughout her colon, all of which are adenomas. She has a history of an acute abdomen secondary to a desmoid tumor and a mandibular osteoma diagnosed as a child.


This condition is caused by mutation of which of the following genes?