Question

The function of a tumor-suppressor gene can be lost in three common ways. Which of the following is NOT one of them?

1) abnormal DNA acetylation near the promoter of the gene
2) a mutation in the coding sequence of the gene
3) the loss of the chromosome that carries the gene
4) None of the above

Answer 1

The correct answer to which listed method is not a way tumor-suppressor genes lose their function is 4) None of the above. All options presented are ways these genes can be compromised, leading to uncontrolled cell division and cancer development.

Step-by-step explanation:

The student asked which of the following is NOT a way in which the function of a tumor-suppressor gene can be lost:

1. Abnormal DNA acetylation near the promoter of the gene
2. A mutation in the coding sequence of the gene
3. The loss of the chromosome that carries the gene
4. None of the above

All the options listed are common ways by which a tumor-suppressor gene's function can be compromised. Therefore, the correct answer is 4) None of the above.

Tumor-suppressor genes are critical for regulating the cell cycle and ensuring that cells do not divide uncontrollably. When functioning normally, these genes slow down cell division, initiate DNA repair mechanisms, and can even trigger cell death when necessary to prevent cancer. When a tumor-suppressor gene is inactivated, cells can multiply unchecked, leading to the development of cancer.



This inactivation could be due to several factors, including mutations in the coding sequence, epigenetic changes such as DNA acetylation that silence gene expression, or even the complete loss of the chromosome where the gene resides.