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Genetic data may help, or reveal too much

Nancy Andrews, dean of the School of Medicine, talks to students Wednesday about diseases based in genetics.
Nancy Andrews, dean of the School of Medicine, talks to students Wednesday about diseases based in genetics.

As personalized medicine becomes more advanced through the use of DNA sequencing, questions arise concerning the dangers created by knowledge of genetically caused diseases.

In a Chautauqua Lecture called “When the Genome Gets Really Personal,” Dr. Nancy Andrews, dean of the School of Medicine, spoke to students about the importance of DNA sequencing in determining a person’s future health issues and the ethical problems that have become a major part of decision-making in this field. She also described the significance that personalized medicine will have in the next five to 10 years.

“Researchers want to find causes for genetic diseases or help patients who have one,” Andrews said. “This creates complicated questions because it mixes research and clinical work.”

She noted several diseases that doctors have been able to link to genetics, including Huntington’s, some forms of cancer and Alzheimer’s, as well as several blood disorders. One such blood disease, called Thalassemia, which is similar to anemia, caused devastating problems on the island of Sardinia in the Mediterranean throughout the 1900s. However, with “very aggressive genetic tests” and precautions doctors advised to patients, eventually they were able to decrease the occurrence of the disorder from one in 250 births to less than one in 4,000.

Andrews called it a “huge public health success,” but also noted that not everyone supports these procedures. DNA sequencing started with the study of eugenics, when researchers found that they could decrease traits considered harmful and increase traits considered beneficial through controlling the breeding of plants and animals.

“People now think a lot about the dark side of eugenics,” she said. “It’s morally repugnant to most people.”

She also noted that some view the topic as a way of “purifying populations” or changing a gene pool.

In today’s world, most genetic analysis is done for the purpose of research, and often children are tested since they generally have no pre-existing health conditions. These screenings, however, can cause some ethical questions to arise if researchers find unexpected results. If doctors discover that a child has an increased risk of cancer, for example, it is unclear what they should tell the parents, Andrews said.

Familial genetic testing can also bring up ethical questions, she added, noting that sometimes patients “will learn that ‘dad’ is not ‘dad.’”

Andrews also commented on the reliability of today’s available technology, noting that genetic tests are not 100 percent accurate.

“It could be very useful information, but if information is wrong, it could be harmful,” she said. “If sequencing is not as reliable, you need to send information to a more qualified lab to confirm that sequence. Who pays for this?”

The procedure costs about $8,000 and often the results are “boring,” she said. Most of the time, researchers do not find anything worrisome. Although each of us has some form of genetic mutation, most are insignificant.

After the lecture, students were left to ponder the ethical questions Andrews raised. Many considered the problems of prenatal screening, which allows parents to discover genetic mutations before their children are born. In turn, this raised questions of the ethicality of abortion. Many students also applied the lecture to their own lives, wondering if it would truly be beneficial to know about their predestined health problems.

“If it’s something I know we can’t cure, then I’d rather not know,” freshman Elizabeth Ginalis said.

Another student in attendance, junior Biqi Zhang, a neuroscience major with a certificate in genome sciences and policy, has had her own genome analyzed. She said she was not worried about the results when she chose to be tested. “Things don’t run in my family, so I didn’t have any worry,” she said.

But after being tested she gained knowledge of her predisposition to some diseases.

“I do have information on certain markers related to Alzheimer’s and breast cancer,” Zhang said. “I don’t regret [taking the test]. I learned things about myself [but] they’re not serious things.”

She also noted that genetics are only one factor in an individual’s health portfolio. Environmental factors also influence one’s development.

Zhang also affirmed one of Andrews’ points, that currently, researchers may not be able to infer much information from the data they collect because the implications of genetic mutations are still being studied.

“Ten years from now we’re going to have a much better understanding of genetics,” Andrews said, adding that for now, much of the human genome is a mystery.

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