Spitomics: The promise and perils of 'personalized' medicine

Posted: March 06, 2013

There's a genetic testing revolution underway at your local hospital. And it's causing doctors and medical students to confront some very thorny issues.

"Personalized medicine" uses genetic information derived from tests to predict a patient's chances of coming down with diseases and offers ways of tailoring some cures.

Could testing on a fetus show that the person has the potential to be autistic? Gay? If so, what will parents do with the information?

A product of a $30 billion effort to sequence the human genome, the tests until recently have been limited to those wealthy enough to pay up to $10,000. But the tests have dropped to about $1,000.

Dr. Art Caplan, a professor of medical ethics at New York University, brought a host of provocative questions raised by the tests and their use in new treatments to Cooper University Medical School in Camden on Tuesday.

The inaugural speaker of the Berkowitz Family Foundation Lecture, Caplan dismissed most of the consumer-targeted versions of the genetic tests - those that claim to match diet and lifestyle to personal DNA - as "ethically worrisome" and "nonsense added to ridiculousness." Others, including 23andMe and DeCodeMe, are "more legitimate," he said.

Caplan, gregarious with a white mop of hair, also spoke about the developing field of pharmacogenomics, the study of prescribing drugs for patients based on their personal DNA.

"It's great, but it's still the early days," Caplan said.

Prenatal testing will drive most of the upcoming controversy, Caplan said.

"We can now test a mother's blood as soon as six or seven weeks into a pregnancy," he said. "That brings some big moral issues."

It's inevitable that the tests will be offered to all expectant mothers and become the standard of care, he said. They may be able to determine the gender of the fetus, whether the child will suffer from diseases, will be autistic, and indicate the likelihood that the child will be homosexual.

If a test indicates a chance of any of those conditions, will the information prompt expectant parents to abort a fetus?

"It will revolutionize how we think about prenatal care," Caplan said. "Gender is not a disease, and neither are other stigmatized conditions.

"We better get ready for panic, disruption and trouble."

One other consideration: just because a test indicates you have a chance of getting a disease, doesn't mean you will get it.

Caplan spoke with Philly.com in a telephone interview before the lecture.

Philly.com: What's the difference between medicine as we know it and personalized medicine?

Caplan: Medicine historically has been a one size fits all activity, especially when it came to testing drugs and vaccines. It has to work on everyone because it's been sold manufactured and delivered on the basis of "this is going to work for all."

Historically we knew that there were side effects, for example, and those were due to biology but we didn't have the tools to do anything about it.

We hoped that people you gave the pills to wouldn't have a bad reaction. Less well known is that even when they get FDA approval, there are medicines that many people don't respond to. They don't metabolize the drugs, for example.

The current revolution has opened up the door to say, we don't have to do one size fits all. We can get the drug in the body and have it do what it's supposed to do.

We're taking medicine, something that was a pretty blunt instrument, and making it fine-tuned.

Q: How likely is it that personalized medicine will deliver on its promises?

A: I think it will deliver on its promises, but not as fast as some optimists are talking about right now.

We've had an explosion of genetic information, we've mapped the genome, we know what makes us up and finding out what makes some people susceptible to certain diseases.

We're so eager to make it work. There are some things we can target. We know some people don't respond well to Coumadin, warfarin, and how to adjust for that. But these are baby steps. There's going to be a lot more personalized and individualized medicine to come, but it's like we're trying to swallow a giant gush of genetic information and it's going to take a while to sort it all through.

Those pitches you see up on billboards? It's not going to be that fast.

Q: Is genetic testing for everyone?

A: I think genetic testing at present is not something everyone should consider. If you have a history of genetic disease, for instance, if breast cancer runs in your family, or if you have a cancer, I would ask a doctor for a test.

For someone who says "I woke up today, and think I better get a gene test" for no specific reason, I don't think we're there yet.

People forget that the actionable things you can do to prevent disease you can do without a gene test: exercise, diet.

You have to test your will first, not your genes.

Q: Who should have access to the tests? So far it seems only the intellegensia and the wealthy can afford to have their genomes sequenced. Should insurance companies pay for the tests?

A: The price is falling. And it's partly due to improvements in computer chips, so analyzing your DNA, it's like putting it in a computer where many small pieces of information are analysed.

It's still a bit of a luxury, but the price is getting down to about $1,000 for each genome. When it gets below ($1,000) insurance should pay. Insurance doesn't need to pay for everyone, but those who have a history of genetic disease in their families they might consider it. For $1,000 in most cases I'd rather send you to exercise, weight watchers or an anti-smoking program.

It's great to find out genetic risks but the things you can do something about, you should. And very few of us do.

Q: Should there be limits on who has access to the data?

A: Yes. However, there's one problem. If you send your spit (for DNA testing) to a company - what I call "spitomics" - they promise you privacy. But we're not sure if they're going to get bought by another company or what would happen if they go bankrupt.

We haven't set up the legal infrastructure to make sure the information doesn't fall into third-party hands because of deals, transactions or government saying it will use the data banks to start prosecuting crimes.

Q: What about the insurance companies? If you have a marker for cancer are you obliged to let them know?

A: The good news is that it used to be of grave concern if you had a preexisting condition, a high gene risk factor for a disease.

But with Health Reform (aka Obamacare) there's less of a risk of losing your health insurance.

There's still some privacy issues, but you can't be excluded from treatment. But it doesn't mean you're going to get all the bells and whistles you might with private health insurance.

It may make it hard for you to buy health insurance, for when they ask "what do you know" (you're obliged to tell them the truth) about your genetic knownledge. You can still be penalized. If you hide it they can void your policy. They're aggressive that way.

But the basic coverage, with Health Reform, now people will be able to get. That opened the door to less fear about the tests.

Q: Should someone who gets a genetic test share the knowledge about an untreatable genetic disease with family members - Alzheimer's, for example?

A: No. They should ask if they would like to know, but not just tell them. Some people don't want to know.

If I was going to get Alzheimer's I would not want to know. For other things, I feel like I want to know so I could plan better, get affairs in order and have a good living will. But I'm the kind of person who doesn't worry. Part of it is a personality style.

Children should not be told, unless there's a therapy that could help them right now. If there's no cure, let them discover that information when they're old enough.

Q: What other ethical dilemmas is personalized medicine and genetic testing creating?

A: One of the most difficult ethical questions is, when you're young and getting married, should you tell your fiancée?

Most people who are in love aren't going to be deterred by the risk factors. I'm sure there are some people who say "I have this risk, but I don't want to say anything." You may decide not to have children if you don't want to pass on serious problems. But these are decisions made in the heat of romance, and those are the hardest. Truth is not usually the hallmark of romance.

Q: Are there cases where someone is tested and finds something unexpected?

A: A long time ago I had a guy come in. His father had Huntington's disease (which causes dementia and death at about age 50) and a very severe case of it. The guy got the test. It was hard to give him the results.

The good news: He didn't inherit that factor.

The bad news: It wasn't his father.

You can find out about paternity when you're tested.

There have been cases that learning about the genetic makeup you realize this patient must be the product of incest. Like I said, there could be very disturbing information that you weren't looking for.

Q: Do you foresee other problems with personalized medicine and genetic testing?

A: Sometimes genetic information to stigmatize a group. We might find that there's a correllation in a particular population with mental illness. There may be higher probable rate, but not everyone has it.

Q: What about prenatal testing?

A: There are questions emerging. You might have someone who says, "if that baby isn't perfect, I'm not going to have that baby."

It's one thing for an individual if there's a risk for diabetes. You think: I should go on a diet. But now you see it in the fetus. Are you going to end that pregnancy because of that risk factor? So it gets much more controversial for not only what you're testing for, but when you're testing.

Q: But having a marker for a disease doesn't necessarily mean you'll get it, right?

A: Yes. It's important to remember that testing usually requires counseling. You can be the hairiest guy in the room, have a marker for baldness, and still not be bald. There's a difference between having the risk and having the disease. There aren't a lot of counselors out there, and we'll need many more. Most doctors and nurses aren't trained for this. There's another challenge with risk information. Genes cause risk, but so do your habits. There was a woman who had concerns about breast cancer. She smoked four packs a day. Habits and environment also make a big difference. Just because you have a clean bill of genetic health, doesn't mean you have no risk factors. Our health is not just in our genes.

Q: Any last words?

A: At the end of the day, if you ask me what's most important factor for disease, it's probably poverty.

I tell people to remember that nobody passes a genetic test, because something is always found. Everyone is mortal. No matter what you do, this is not a test you can pass.


Contact staff writer Sam Wood at 215-854-2796, @samwoodiii or samwood@phillynews.com.

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