Biology of Humans 6th Edition by Judith Goodenough,Betty McGuire

Exercise 9

In this chapter we have seen two ways that gene activity can be altered. One way is through changes in the genome, the sequence of nucleotides in DNA. A more recently recognized way to modify gene activity is to alter the epigenome, the system of proteins and chemicals that can bind to DNA and turn genes on or off. In the next chapter, we will learn that both types of genetic alteration can lead to cancer. The following is an excerpt from a report by Esha Dey on LiveScience.com1 regarding a study published in JAMA Oncology2 on epigenetic changes in cheek cells associated with smoking. You can read Dey's entire news report here: http://www.livescience.com/50857-cancer-signs-cells-epigenome-smoking.html "Smoking may bring on changes in cells that are linked with many cancers, including breast and gynecological cancers, a new study finds. These changes could provide an early warning sign of cancer, particularly in cheek cells, the research showed. "Researchers analyzed cheek swabs from 790 women, and found those who smoked were more likely to have certain changes associated with these cancers, which people may not realize are linked with smoking... "In the study, the researchers analyzed the epigenetic changes within cells, and found a "signature" of smoking. By looking for this signature, the researchers found they could differentiate between normal and cancerous tissue with near absolute certainty, including cancers in other parts of the body. "The signature could also be used to predict if a pre-cancerous lesion would progress to a full-blown invasive cancer, the researchers said. "The ability to quickly and easily identify such changes in cells could help doctors to predict and prevent cancers, the researchers said."
Today we can do genome sequencing and epigenome mapping at a reasonable cost. Using reliable sources, find other genomic or epigenomic alterations with a specific disease of your choice. Do these disease-associated genetic changes have implications for prevention or treatment Cite your sources.