Identify the normal functions of the following genes whose mutations are associated with the development of cancer.
APC(familial adenomatous polyposis)

Verified step by step guidance

1. Understand that the APC gene is a tumor suppressor gene, which means its normal function is to regulate cell growth and prevent uncontrolled cell division.
2. Recognize that the APC protein plays a crucial role in the Wnt signaling pathway, where it helps regulate the levels of β-catenin, a protein involved in gene transcription that promotes cell proliferation.
3. Note that the APC protein forms a complex that targets β-catenin for degradation, thus preventing excessive cell growth and maintaining normal tissue homeostasis.
4. Realize that mutations in the APC gene disrupt this regulatory function, leading to accumulation of β-catenin and uncontrolled cell division, which contributes to the formation of familial adenomatous polyposis and increases cancer risk.
5. Summarize that the normal function of the APC gene is to act as a gatekeeper by controlling cell proliferation through the degradation of β-catenin, thereby preventing tumor development.

Key Concepts

Tumor Suppressor Genes

Tumor suppressor genes produce proteins that regulate cell growth and division, preventing uncontrolled proliferation. When these genes mutate, their regulatory function is lost, leading to increased cancer risk. APC is a classic example of a tumor suppressor gene involved in colorectal cancer.

APC Gene Function

The APC gene encodes a protein that helps regulate cell adhesion and signal transduction pathways, particularly the Wnt signaling pathway. It controls the degradation of beta-catenin, preventing excessive cell proliferation. Mutations in APC disrupt this control, promoting tumor formation in the colon.

Familial Adenomatous Polyposis (FAP)

FAP is an inherited disorder caused by germline mutations in the APC gene, leading to the development of hundreds to thousands of colorectal polyps. Without intervention, these polyps have a high likelihood of progressing to colorectal cancer, highlighting the importance of APC in maintaining normal colon cell growth.