Could the cosmetics in your purse be harmful to your health? Image from Wikimedia Commons. / CC BY-NC 3.0

Each October, within Breast Cancer Awareness Month, my friends and I get into a flurry organizing and putting on Beats for Boobs. Beats for Boobs is an annual fundraiser started by my friend Juliana Cochnar after finding out her mother was diagnosed with Breast Cancer. The Beats for Boobs mission is to educate the community on breast cancer through a collaborative celebration of art, fashion, food and music.

This year the fundraiser welcomed 1200 people through its doors and raised over $20,000 for local Breast Cancer organizations. The theme this year was Green is the new Pink. The education team, which I have been a member of for three years, now, was tasked with educating the public on ways to prevent breast cancer. We set up a prize wheel and gave everyone a chance to win; all they had to do was answer a question about Breast Cancer correctly.

Some of the questions posed were:

Question: Synthetic Chemicals can accumulate in body fat and remain in breast tissue for decades- some that can cause mammary tumors.

TRUE/FALSE

Answer: TRUE

Question: 80,000 chemicals have been registered for use in the United States in the last 40 years, yet _________ of them have been fully tested for their effects on our health.

10%
25%
50%
5%

Answer: 10%

Question: No more than _______ women who have Breast Cancer have a genetic history of the disease.

1:5
1:3
1:8
1:10

Answer: 1:10

Question: Which of the everyday products below can contain chemicals linked to breast cancer?

Shampoo
Deodorant
Face Cream and Make-Up
Sunscreen
All of the above

Answer: All of the above

Most of the night, I was stationed at the What’s in Your Purse Table, which used the Skin Deep: Cosmetic Safety Database Website to access the hazard of everyday products. “Now in its fourth year and third major update… Skin Deep database provides you with easy-to-navigate safety ratings for nearly a quarter of all products on the market — 52,099 products with 8,799 ingredients. At about one million page views per month, Skin Deep is the world's largest and most popular product safety guide. The database rates items on a 1 to 10 scale – 0-2 is low hazard, 3-6 is a moderate hazard, 7-10 is a high hazard. After the fundraiser, I became very well acquainted with the Skin Deep website. I went through every cosmetic item in my house and as a girl with a love of make-up that meant quite a few items! Most of the items I was using on my face were a moderate to high hazard rating. The toothpaste I used had a rating of 7. The eyeliner I used on a daily basis had a rating of 9 and the lip-gloss I wore nearly everyday had a rating of 6. At the end of my research, I had found out that my mineral make-up was low hazard but my eye shadows, sunscreen, soap and toothpaste had to go. I got rid of a full shopping bag of products that all rated 5 and above. I called my mom and told her what I found out. I am bringing over my laptop and we are going through her bathroom and toiletries next week.

Each year, on the education committee for Beats for Boobs we try to make the education fun and accessible so we can instill ways to prevent Breast Cancer. The Skin Deep website was an excellent resource to do just that. Only one person was able to get something out of it this year but I am hoping that with this blog and a new approach next year, that number will continue to rise.

This blog is in honor to my Aunt who is surviving Breast Cancer.

"Mysteries of DNA" image courtesy Mark H. Adams. Full-size version.

As anyone who follows this blog knows, I recently took a 23andMe genetic test and have been blogging about it ever since. Today I thought I would focus on one of the fun parts of the service: traits.

Lots of our traits are at least partly dependent on our genes. So a genetic test should be able to tell me a bit about what I’ll look and even be like in the future. It may even tell me what I can expect for my kids.

Here is what is available on the 23andMe test (click on the image for a larger version):

As you can see, some of this is pretty obvious…I know my eye color for example. It is kind of cool to see my blue eyes written in my DNA but not necessarily that helpful. When I click on eye color, I find out that people with this particular bit of DNA have a 72% chance for blue eyes, a 27% chance for green and a 1% for brown. (Incidentally, this 1% brown is probably a big reason why blue-eyed parents can have a brown-eyed child.)

What would have made this report more interesting for me is what it meant for my kids’ eye color. Does it mean I’ll have blue-eyed kids? This of course depends on my wife’s genes but it would be cool to have the option of including my wife’s data to find out.

Other less obvious traits were very interesting to me. The results say that like most mammals, I should be lactose intolerant. Which I am not—I’m fine drinking milk. So did 23andMe get it wrong?

Probably not. The science is pretty good on this topic. People with a certain difference in their lactase gene almost always lose the ability to make lactase as adults. No lactase means lactose intolerance.

When I dug deeper on the website I got some hand waving about other genetic influences or the environment. A better explanation is that I will probably become lactose intolerant at some point in my adult life—it just hasn’t happened yet.

Losing the ability to make lactase is a gradual thing. It happens to some people early in adulthood and others later on. I am probably one of the “later ons.” Something to look forward to…

One trait that I’ve always been a bit interested in is HIV resistance. Some people are more resistant to infection by HIV (the virus that causes AIDS). If these people do become infected, they tend to develop AIDS symptoms much more slowly as well.

In Europeans at least, this resistance has been tied to a DNA difference called CCR5-delta32. The people who are resistant to infection and who develop AIDS more gradually tend to have two copies of this DNA difference.

This DNA difference has been proposed to have become common in Europeans because it also makes people resistant to either the plague or smallpox. If true, my ancestors must have died like flies from the plague or smallpox because I don’t have the DNA difference.

I also now know about what my DNA tells me about my earwax, how I respond to a certain bitter chemical, and whether I flush from alcohol. These are sort of interesting but not very.

This part of the 23andMe experience is kind of fun though. I really enjoy it when genetic theory matches up with what I can see about me. It sort of validates genetics…

What can genetic testing tell you?

A while back I took a 23andMe genetic test that looks at over 600,000 different spots on my DNA. The last few blogs I have been going over my genetic test results with an eye on how useful they are. And how well the results are explained.

Last blog I wrote about how current genetic tests aren’t that great at predicting your risk for common, complicated diseases like diabetes or Alzheimer’s. This time I thought I’d focus on what today’s genetic tests can be very good at and whether or not 23andMe does a good job with these.

Current genetic tests are very good at predicting your risk for rare, simple genetic diseases like cystic fibrosis (CF) or Huntington’s disease (HD). And at predicting the chances that your kids will get these diseases too.

Genetic tests for these diseases work because most of them are caused by a single gene gone awry. Testing for a single gene is relatively easy.

For example, most cases of CF happen because of known differences in the CFTR gene. A genetic test can look for these differences and tell you if you and/or your spouse have any of them. If you both do, they can also give you a pretty good idea about the chances that your kids will get them too.

Of course, we don’t know all of the differences in the CFTR gene that can cause CF. And some differences only cause CF some of the time. And there are people with everyday, run-of-the-mill CFTR genes who get CF because of differences in different genes.

Still, as genetic tests go, these are pretty good. If a test comes up with a known CFTR difference that causes CF, then you have a pretty good idea of what your chances for developing CF are. If your spouse gets tested too, then your kids’ chances can be determined as well.

So how does 23andMe do? OK, I guess…

First off, they look at eight of these sorts of diseases under a category called Carrier Status. The diseases they look at are shown in this image:

For me, the first big result is that I am a carrier for a variant that can lead to hemochromatosis. This isn’t surprising since 1 in 8-12 people of Northern European descent in the U.S. are too, but it is definitely something to watch out for. It may be important for my wife to be checked too so we can make sure none of our kids got two copies. (Luckily hemochromatosis is easily treated by giving blood on a regular basis.)

Some of the other results are less illuminating. For example, I do not carry the CF difference they test for (delta F508). This is of course great news. Unfortunately, this variant only accounts for about half of the CF cases out there. Which means I could be a carrier for CF, just not a carrier of the most common variant that they happen to test for.

The same thing goes for most if not all of the other carrier status diseases (sickle cell anemia is an exception). Some like BRCA (breast cancer) are as poorly covered as CF while others like Bloom’s disease cover a larger percentage of cases.

23andMe is pretty upfront about the limitations of their testing once you dig a bit into the results. But still, if they’re going to look at 600,000 different parts of my DNA, you’d think they could add a few more to give me a stronger answer about whether or not I am a CF carrier.

Luis Medellin and Karl Tupper set up a drift catcher in Lindsay, CA.

My radio story on pesticide drift looks at how residents in the citrus town of Lindsay are monitoring pesticides in the air and in their bodies. They are using a device called a Drift Catcher, modeled after technology used by the California Air Resources Board and the Department of Pesticide Regulation.

The pesticide drift catcher has a vacuum pump that sucks air into a glass test tube, where pesticide residues are trapped in a resin. Community members change out the test tubes and send them to a lab, where scientists crack them open, extract the residues with an organic solvent, and then analyze those extracts through gas chromatography.

The Lindsay study measures Chlorpyrifos, a pesticide that can cause headaches, blurred vision, and muscle weakness when people breathe in the air from a recently-sprayed orchard or field. Studies also show prenatal exposure MAY have effects on children's cognitive and motor skills.

Environmental lawyers are using preliminary data from the Lindsay drift catchers in a petition asking the EPA to create pesticide buffer zones around schools, child care centers, and hospitals.

Listen to the Catching the Drift – Part Two radio report online.

Editor's Note: This week we have the first of two special reports on pesticide drift.

In this week's Quest radio piece, I talk to two pregnant organic onion workers who got sick after an apple farmer sprayed pesticides on a nearby orchard. Following a nearly three month investigation, the Kern County Ag Commissioner issued citations finding both the apple grower and the organic company at fault (see the citations here and here). Workers told me that even after the drift started, the organic farm's supervisor encouraged them to keep bunching onions, telling them to put handkerchiefs over their mouths to block out the smell of the insecticides.

Whenever a big pesticide drift accident like this happens, it raises important questions: How often do these kinds of incidents occur? Are things getting better for people in communities near where pesticides are sprayed?

That's hard to tell, because of the way the Department of Pesticide Regulation (DPR) and County Ag Commissioners keep track of the data. There's no single enforcement code to categorize incidents as "agricultural drift affecting humans."

DPR does keep a statewide database of acute illness related to pesticides, as documented in worker’s comp or physician's records. Pesticide activists say those numbers are low, because many victims don't see a doctor. And doctors don't always know how to recognize symptoms of pesticide illness, or that they are supposed to report those cases.

And here's another twist: back in 2000, DPR changed its criteria for how it evaluates pesticide illness. So you can't compare the number of incidents from the 1990s with incidents today. All that makes it very difficult to determine if growers and regulators are really doing a better job keeping the public safe from chemicals drifting off the farm, especially after the passage of bills like the 2004 law sponsored by State Senator Dean Florez.

While that law clarified rules for emergency responders and required growers to pay medical bills for uninsured victims, it doesn't seem to have led to a dramatic drop in pesticide drift incidents.

In 2006, Governor Arnold Schwarzenegger vetoed a bill that would have sped up pesticide drift investigations and increased penalties. Instead, he directed DPR to streamline the enforcement guidelines for counties. Ag Commissioners can now issue a maximum fine of 5,000 dollars for each person sickened by pesticide drift.

That's a penalty some advocates, like Californians for Pesticide Reform think is far too low to act as a deterrent.

Meanwhile, County Ag Commissioners are facing budget cutbacks that may shrink their enforcement teams. Many agriculture commissioners already have just six or seven pesticide enforcement inspectors to police thousands of farms.

The Department of Pesticide Regulation says it can't enforce the law unless drift incidents are reported. The department has launched a new campaign to educate fieldworkers about pesticide drift, printing up wallet-sized cards with a toll-free hotline number in English and Spanish.

Listen to the Catching the Drift radio report online.

Could a genetic test have told me I was at a higher risk for developing type 2 diabetes? Image source: aldenchadwick

Metabolic syndrome isn’t quite as scary as it sounds.  Basically I am on my way to type 2 diabetes.  But if I eat better and get off the couch, I should stave off the disease and get better.

My question, naturally, is whether or not a genetic test could have told me I was at a higher risk for developing type 2 diabetes.  And whether I would have done anything with that result.

As you know if you’ve been following my blog, I took a 23andMe genetic test and have been writing about it since.  The image below shows what the front page of my clinical report looks like (click to enlarge):

According to the DNA checked in this test, I am in the average risk range for type 2 diabetes.  This doesn’t really seem to line up with my reality.  But I might not expect it to since these genetic tests are so limited right now.

This kind of test can be informative with the yes answer—yes I carry a certain version of a gene that might lead to a disease.  But the no answer isn’t that useful.  It doesn’t mean that they've looked at all the possible genetic differences that can lead to a disease and I don’t have any of them.  Basically it means that they didn’t find the specific genetic difference they were looking for.

Now I wouldn’t necessarily have predicted that any genetic test available right now could tell me a lot more than that.  Type 2 diabetes is too complicated for that and a whole lot more research will need to be done to get a genetic test useful to lots of people.

But still, this is probably what people are looking for with these sorts of genetic tests.  Will I get cancer, type 2 diabetes, Alzheimer’s, Parkinson’s, etc.?  For most of these cases, the tests can tell you a lot about rare forms of these diseases but little about the more common forms.

So the no answer didn’t really help me much.  Here I am on my way to being a diabetic and the test said I was at average risk.  Of course, I suppose I didn’t even need to take a test… all four of my grandparents came down with type 2 diabetes.  Like lots of these complex diseases, family history is the best predictor.

The second part of my question is a hypothetical one.  Let’s say they had a perfect genetic test that said that I was at an increased risk for type 2 diabetes.  Would it have changed my behavior?  I’m not sure but probably not.

I certainly wouldn’t have changed any of my behaviors when I was young.  I was invincible, remember?

Now that I’m a bit older, such a test might have influenced my behavior a bit.  I already knew about my risk because of my grandparents but my thought has always been that maybe I got lucky and didn’t inherit their tendencies towards diabetes.  But if they were tested and we shared the same genetic differences that led to type 2 diabetes, then I might be worried enough to change what I was doing.

Most likely though, my behavior modification wouldn’t be perfect.  What I’d probably do is keep watching TV and eating Twinkies but get my blood sugar tested more often.  Once I was headed for diabetes, then I’d modify my behavior and keep it at bay.  (I’m sure doctors scream into their pillows at night because of patients like me.)

This is different than some people’s reactions to other genetic tests.  For example, some women who find out they have the version of BRCA1 that greatly increases their chances of breast and ovarian cancer have a double mastectomy and/or a hysterectomy before there are any signs of cancer.

I might react much more strongly with a valid cancer genetic test.  Cancer is scary, nasty and not really reversible.  Type 2 diabetes is different.  You can start down the road, modify your behavior and then nip it in the bud.  Carpe diem and then pay the piper.

Mercury is a poisonous metallic element that is liquid at room temperature.

There's nothing like producing a controversial story on some favorite food group to have a profound effect on one's appetite. I gave up chicken after doing a story on factory farms (I already didn't eat beef or pork or I would have eliminated those as well.) Now, fish, too, has fallen from grace. Ignorance was bliss.

I've known for quite some time that some fish, especially tuna, were high in mercury. But discovering the extent of the problem, and that halibut and sea bass were also on the “do not eat too much of” list, was eye-opening for me. Now I count fish servings like some people count calories. Japanese cuisine, one of my favorites, has lost some of its glow, as well as its frequency in my dining-out plans.

Many of you have practical questions, as did I. How big a crimp does this have to put in my diet? How much is too much? How often is too often? Can I still enjoy that tuna sashimi and not worry about mercury overload?

Because there wasn't time in the QUEST TV segment on mercury in the bay to include information on safe fish eating practices, below are the guidelines, along with web links, to help you get plenty of Omega 3s and still keep your mercury levels low.

Here's what California's Office of Environmental Health Hazard Assessment says about eating fish from the San Francisco Bay and Delta Region.

• Women beyond childbearing age and men should eat no more than two meals per month of San Francisco Bay sport fish, including sturgeon and striped bass caught in the delta. (One meal for an adult is about eight ounces).
• Women beyond childbearing age and men should not eat any striped bass over 35 inches.
• Women of childbearing age, pregnant, nursing mothers, and children should not eat more than one meal of Bay fish per month. In addition, they should not eat any striped bass over 27 inches or any shark.
• This advisory does not apply to salmon, anchovies, herring, and smelt caught in the bay; other sport fish caught in the delta or ocean; or commercial fish.
• Richmond Harbor Channel area: In addition to the above advice, no one should eat any croakers, surfperches, bullheads, gobies or shellfish taken within the Richmond Harbor Channel area because of high levels of chemicals detected there.

Here’s a summary of the joint fish advisory published by the FDA and EPA for women who are pregnant, breastfeeding or may become pregnant and for children. This is a general advisory not exclusive to any water body.

• Do not eat Shark, Swordfish, King Mackerel, or Tilefish because they contain high levels of mercury.
• Eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in mercury. Five of the most commonly eaten fish that are low in mercury are shrimp, canned light tuna, salmon, pollock, and catfish.
• Another commonly eaten fish, albacore ("white") tuna has more mercury than canned light tuna. So, when choosing your two meals of fish and shellfish, eat only up to 6 ounces (one average meal) of albacore tuna per week.
• Check local advisories about the safety of fish caught by family and friends in your local lakes, rivers, and coastal areas. If no advice is available, eat up to 6 ounces (one average meal) per week of fish you catch from local waters, but don't consume any other fish during that week.
• Follow these same recommendations when feeding fish and shellfish to your young child, but serve smaller portions.

Also, check for local advisories for each water body in California that has fish consumption guidelines. They vary by water body.

And lastly, here’s some practical advice from Dr. Jane Hightower, the medical doctor who we feature in the mercury story.

• “If you’re genetically susceptible, it’s really important to know that if you are an autoimmune-prone patient, Lupus, MS, thyroiditis, these kinds of things, then you should not consume mercury on a regular basis or at all. … And then the cardiac patients. You know, mercury can cause a reaction in vessels that leads to inflammation. So you want to have your Omega 3 fatty acids, which is anti-inflammatory. And not have mercury which is pro-inflammatory…. If you want to avoid significant mercury and you just don’t know what the mercury content is in the fish, a rule of thumb is to eat the small fish. Not a piece of the fish. If it comes in a steak, you want to know how big the fish was that the steak came from. You want the whole fish to fit on your plate. Don’t buy a bigger plate. Get a smaller fish. With the exception of salmon. Salmon can have elevated mercury, but very rarely.”

Good luck, good health, and and watch out for bones!




Watch the Mercury in San Francisco Bay television story online.





Tags: almaden, gold rush, mercury, mining, poison, pollution, total maximum daily load, toxic
]]> http://www.kqed.org/quest/blog/2009/10/06/producers-notes-mercury-in-san-francisco-bay/feed/ 3 37.8627 -122.318 http://www.kqed.org/quest/blog/2009/10/02/reconnecting-science-religion-and-health-care/ http://www.kqed.org/quest/blog/2009/10/02/reconnecting-science-religion-and-health-care/#comments Sat, 03 Oct 2009 04:55:11 +0000 Jim Gunshinan http://www.kqed.org/quest/blog/?p=3770 Original photo by: astique I have been thinking a lot about science and religion, in part because of the debate over health care, with people of different religious convictions coming out on both sides of the issue. Do we support individual rights by keeping government out of health care? Or do we ensure some measure of equality and community by moving health care out of the for-profit business model through more government involvement? In a religious sense, the first group may value a personal, transforming relationship with God, while the second may base their opinions on a sense of the religious call to work for the common good, with a special concern for the poor and the powerless. I won’t venture my position here, though if you have read my previous posts you may make a good guess.

What seems missing from the debate, in my opinion, is science. I hear a lot of ideology coming out of Washington and being espoused at town hall meetings and by protesters on both sides of the issue. I don’t hear much from people who have studied various health care systems and have gathered good information about what systems work and why they work and how to practically adapt such systems in the United States.

I think that science is fundamentally about information and religion is fundamentally about relationship. The word religion comes from the Latin "to reconnect." Immanuel Kant wrote in The Critique of Pure Reason that human reason has gone from the position towards nature as that of a pupil before the teacher, to that of a judge before a witness. In other words, science has become more about information and less about a basic curiosity and respect and even love for nature. On the other hand, religion has become more and more self-centered. When Catholic Bishops care more about the reputation of the Church and less about the welfare of the poorest and most vulnerable in their communities, we have a problem. When popular preachers use their influence to push a particular political agenda, while enriching themselves in the process, we have a problem.

I don’t know how the debate about health care will turn out, but I do have an example of how it can work. I take medication for a chronic condition, and see a doctor two or three times a year to discuss my medication, make adjustments, and so on. With her help I have been able to live a pretty healthy and fulfilled life. She spent years in medical school working very hard to gather information about the human body, its deceases, and its cures. She has spent many years gaining experience in applying that information in particular cases. But when I see her there is more going on then the passing of information. I believe she cares how I am doing. I think, within the boundaries of her profession, that she loves me, as she does her other patients with whom she has been able to build a relationship over time. However the health care debate turns out, I hope it allows more people to have the kind of relationship I have with my doctor. And I hope that it encourages more doctors to be healers, and not just dispensers of information and pills.


Tags: caring, emmanuel kant, god, government, health care, reconnect, reform, religion, Science
]]> http://www.kqed.org/quest/blog/2009/10/02/reconnecting-science-religion-and-health-care/feed/ 0 37.8686 -122.267 http://www.kqed.org/quest/blog/2009/09/28/genetic-tests-when-no-means-maybe-part-2/ http://www.kqed.org/quest/blog/2009/09/28/genetic-tests-when-no-means-maybe-part-2/#comments Mon, 28 Sep 2009 21:18:10 +0000 Dr. Barry Starr http://www.kqed.org/quest/blog/?p=3737 Are they related to me? I still don't know…When last I left you, I was searching for my great-great grandmother’s DNA in my own DNA.  Remember, legend has it she was Cherokee and I wanted to confirm the legend with a genetic test from a company called 23andMe.

In my last blog post, I showed how the two most powerful ancestry tests, mitochondrial DNA (mtDNA) and Y chromosome, were useless to me in my hunt. Now I want look at the rest of my DNA.  So here we go!

The Y chromosome and mtDNA are a small fraction of my DNA—something like 0.8% of the total DNA in one of my cells.  But they are incredibly useful because they change very little from generation to generation.  The mtDNA I got from my mom is probably exactly like hers.  Same with most of the Y I got from my dad.

The other 99.2% of my DNA is a lot trickier to look at from an ancestry perspective because it has changed a lot from generation to generation over time.  For example, the chromosomes I inherited from my parents are not the same as the ones they have.  I got a mix of their chromosomes

For example, my mom had two copies of chromosome 1 (and two copies of her other 22 chromosomes too).   As you know, she passed one chromosome 1 to me (my dad gave me my other one).  But, through a process called recombination, her two copies of chromosome 1 swapped DNA so that I got a hybrid of her two copies.  I inherited a unique chromosome never before seen.

This is all well and good from a survival of the species point of view, but it is a problem for ancestry testing.  Imagine that instead of my mom, we look at my Cherokee great-great grandmother.  She has just had a child who inherited a mix of her chromosome 1’s.  This chromosome will look Native American and the child would appear half Native American.

Actually, the test isn’t perfect yet and so there isn’t yet a “Native American” set per se.  Instead, here is how 23andMe describes Native American DNA in their tests:

“…people who identify themselves as Native American exhibit fairly consistent Ancestry Painting proportions of about 75% Asian and 25% European, plus or minus 10%.”

This means the chromosomes the child got from his or her mom won’t look Native American but instead will look 75% Asian and 25% European.  (See a realted post of mine elsewhere for why it looks like this.) Now imagine that this half Native American child grows up and has my grandfather as his or her son.

My grandpa will inherit a mix of his parents’ DNA too.  In this case the Native American DNA will mix with the European DNA to create a hybrid.  On average, you would now see something along the lines of 37.5% Asian (this is a simplification but it gets us into the ballpark of the number we might expect).

Each generation would see, on average, a continued dilution of this Asian part.  My dad would have 18% Asian, I would have 9%, etc.  Here are my ancestry results (click the image to enlarge):



Not a hint of Asian.  Looks like my great-great grandma wasn't Cherokee.  Or was she?

There are lots of ways she could still be Cherokee.  First off, I don’t know how solid the 75% number is for all Native Americans.  I don’t know how many Native Americans are in their database.  I also don’t know how much variation there will be tribe to tribe.

Secondly, you may have noticed that I was very careful to always say, “on average.”  This is because the recombinations don’t have to be a 50-50 swap.  It is true that if you look at a large number of recombination events, the average will be 50%.  But individual recombination events can be biased towards one or more chromosomes.  Occasionally you’ll get mostly one chromosome and sometimes mostly the other.

Sort of like flipping a coin—do it enough and you’ll get pretty close to half heads and half tails.  But if you flip a coin twice, you might get one head and one tail.  And you might not.  Half the time you’ll get two heads or two tails.

This is less a problem than you might think with our chromosomes since the recombination is spread over 23 pairs with each pair being independent of the others.  But it can still throw a monkey wrench into the works.  23andMe actually has a nice chart that hints at this by giving the most likely range of possibilities.  Unfortunately, this chart didn’t come up with my results and I had to stumble on it while I was playing around.

Using the chart, I can see that the bottom end of my expected results in 0.24% “Native American” (if I am reading the chart correctly).  That is pretty low and it seems like a pretty minor mistaken assumption at the beginning might knock this down to zero.

So where am I after this?  Still in the dark.  This is actually how many genetic tests end up.

The positive result tells you a lot.  Had there been Native American DNA, that would have been a slam dunk.  (This isn’t always the case with genetic tests but it would be here.)  But there wasn’t.  Which means, given that I was on the edge of detection, that she may or may not have been Cherokee.

Now, this isn’t 23andMe’s fault.  The test itself couldn’t be conclusive given how far back we need to go and the DNA tests that 23andMe offers.  In fact, 23andMe does an excellent job of presenting the data.  There are pretty chromosome paintings, graphs superimposed on world maps, etc.  All very nice.

I am still worried that the explanations that go along with these images assume an awful lot of knowledge that most people might not have.  Without that knowledge, it can be hard to assess the significance of a certain result.  Next blog that’ll become even more important as I tackle health conditions.


Tags: 23andme, ancestry, cherokee, dna, genes, genetics, mitochondria, mtDNA, recombination, y chromosome
]]> http://www.kqed.org/quest/blog/2009/09/28/genetic-tests-when-no-means-maybe-part-2/feed/ 3 37.33161018170129 -121.89019918441772 AncestryPainting http://www.kqed.org/quest/blog/2009/09/22/producers-notes-illumniating-depression/ http://www.kqed.org/quest/blog/2009/09/22/producers-notes-illumniating-depression/#comments Tue, 22 Sep 2009 18:37:48 +0000 Sheraz Sadiq http://www.kqed.org/quest/blog/?p=3301 Zoloft is a popular drug used for the treatment of depression symptoms.

Depression is hardly new. The Roman physician Galen, in the second century A.D., expounded on the prevailing medical view that four bodily fluids, or humors, existed within all people but that the unique variation of these humors within people resulted in individual differences among people in their behavior and temperament. An excess of black bile, for example, indicated a melancholic personality.

Fortunately, a lot of scientific progress has been made since then in understanding depression to be an organic, brain-based medical condition that afflicts millions. In fact, an individual has a ten to fifteen percent lifetime risk of developing a major depressive episode. But as Dr. Karl Deisseroth, a Stanford neuroscientist and psychiatrist, told me during our interview for “Illuminating Depression”, “Diagnosis is a big challenge because in psychiatry, we don’t have a lab test. There’s not a blood draw that you can do as you might to check how your liver is doing or how your thyroid function is doing.” So given that the diagnosis of depression is based on clinical observation (most often done by a primary care physician), one can’t help feel that hard, empirical understanding of depression is somewhat lacking, especially when compared to diseases of other organs like the heart and lungs where tests do exist to gauge the presence of pulmonary and cardiovascular diseases.

This was the most interesting observation for me when working on this story. Imagine a medical disease that afflicts eighteen million people in the U.S. (26 million if you include Bipolar Disorder), for which more than 160 million prescriptions were filled in 2008, that is one of the leading causes of disability in the U.S., but a disease for which no definitive medical model of pathology exists. Increasingly, doctors are prescribing antidepressants to treat not just depression but a host of other medical conditions, including chronic pain and insomnia, some of which can co-occur with depression. Sure, we’ve made strides since the time of Galen’s bodily humors and the Freudian view of misplaced hostility and mourning to explain depression, but in some respects, we’re still in the dark about why some people get depression while others don’t, why some people respond to one treatment and not another, or why one person will suffer from a form of depression that is less or more severe than another person. This lack of clear, empirical understanding comes at an awful price to victims of depression, as they encounter remarks from people that tell them to “snap out of it”, implying that they somehow can control the emotional crumbling and dark ideations that accompany the disease.

The consequence of all this is that it’s incredibly tough to create effective, lasting treatments for the disease if we can’t exactly track how the disease affects not only specific regions of the brain but the activity among individual brain cells in regions that may not have even been known to play an integral role in the disease. My layperson’s view is that treating depression currently is a bit like bringing in a car to the mechanic and telling him to fix it but there’s a catch – the mechanic can’t get under the hood to observe directly what’s wrong with the car. We suspect that the problem is with the engine but good luck with opening it up and peering into its pistons. So the mechanic attempts to work on the engine but indirectly, and whatever repairs are attempted may affect the engine but they may also have unwanted effects on the car’s transmission, muffler, timing belt, etc.

Fortunately, advances in imaging techniques like two-photon microscopy and fMRI are elucidating the activity of the depressed brain, allowing the previously impenetrable forest of billions of neurons to be explored, to see their pathways altered, their branches pruned by the disease. And scientists like Philippe Goldin and Kelly Werner are compiling biomarkers like DNA and brain blood flow activity to see if those biomarkers can help predict if people suffering from anxiety and/or depression will respond more favorably to cognitive behavioral therapy than to mindfulness meditation, for example. Dr. Deisseroth is using genetically engineered, photosensitive proteins implanted into rodents’ brains to control brain activity at the level of individual neurons.

Dr. M. Bret Schneider told me during our interview, “A real cure for depression is gonna involve being able to selectively affect those portions of the brain which don’t function properly in depression… But fathoming the huge number of possibilities in each brain with every brain being a little bit different than every other one, is gonna require individualized solutions and will be a scientific feat.” I suppose that with a disease as complex as depression, where one’s individual genetic makeup can influence the kinds of side effects one may experience with an antidepressant, it’s apropos that the future of treating and eventually curing it will entail personalized medicine. Until then, let’s hope that more people bring psychiatry into the research lab to study illnesses like depression, for it’s only through the methodical rigor of science that we have the best hope for curing depression.




Watch the Illuminating Depression television story online.





Tags: brain, depression, drugs, ECT, KQED, optogenetics, QUEST, Stanford, TMS
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