Kaplan Nursing Entrance Practice Exam

What type of mutation can cause cancer?

1. Inherited mutations

2. Somatic mutations

3. Environmental mutations

4. Genetic drift

The correct answer is: Somatic mutations

Somatic mutations are alterations in DNA that occur after conception, specifically in non-germline tissues. These mutations are acquired during an individual's lifetime and can result from various factors such as exposure to environmental toxins, radiation, or errors that occur during cell division. Unlike inherited mutations, which are passed down from parents to offspring and are present in the germ cells, somatic mutations develop in specific cells and are not passed on to future generations. When these mutations affect oncogenes or tumor suppressor genes, they can disrupt the normal regulation of cell growth and division, potentially leading to cancer. This is particularly relevant in understanding how certain cancers develop, such as melanoma, lung cancer, and many others, where the proliferation of mutated cells leads to tumor formation. While inherited mutations play a significant role in some cancers, it is the somatic mutations that accumulate over time in individual cells that are pivotal in the majority of cancer cases, emphasizing the importance of environmental influences and accidental genetic changes in cancer pathogenesis.