As part of a cancer research project, you have discovered a gene that is mutated in many metastatic tumors. After determining the DNA sequence of this gene, you compare the sequence with those of other genes in the human genome sequence database. Your gene appears to code for an amino acid sequence that resembles sequences found in some serine proteases. Conjecture how your new gene might contribute to the development of highly invasive cancers.

Video transcript

Hi everybody. Let's take a look at this practice problem together. Which of the following phrases best describes how genes play a role in invasive cancer. Recall that invasive cancer is cancer cells that are spreading beyond the sight of origination. So, let's take a look at our options. We've got a a single gene mutation is always sufficient to result in invasive cancer. This is a false statement. Typically it is multiple mutations in multiple genes accumulated over time. Single mutation may increase the likelihood of getting cancer, but by itself is usually not enough to cause cancer. Next, we're going to take a look at see gene mutations are only important in the early stages of cancer formation and are unimportant and invasive cancer. This is also an incorrect statement. Gene mutations are important in the early stages of cancer formation and are important in invasive cancer and this is by contributing to cell spreading. Now let's take a look at de invasive cancer is caused by mutations in non coding regions of the genome rather than encoding regions. So this is also a false statement, mutations that cause invasive cancer can occur in both coding and non coding. An example of this is a proto uncle gene that codes for molecules involved in normal cell growth. If mutated, it can become an uncle gene and potentially cause cancer. So D is also incorrect. So our answer therefore has to be B option B. A combination of genetic and environmental variables contributes to the development of invasive cancer. We already know that mutations contribute to invasive cancer, but environmental factors do as well. An example of this is tobacco smoking. It's an environmental factor that can lead to DNA damage and cause invasive cancer. Therefore, B is the correct answer. Alright, everybody. I hope you found this helpful, and I'll see you soon for the next practice problem.