Stem Cell Research Provides New Approach to Study Bipolar Disorder

 

Researchers have detected mitochondrial abnormalities, and differences in neuronal firing, in young neurons from patients with bipolar disorder by using induced pluripotent stem-cell (iPSC) technology. These stem cells are created from patient’s skin cells (fibroblasts) or from patient’s white blood cells (lymphocytes). It is possible to take skin cells or white blood cells and reverse engineer them back to the state where they have the ability to grow into different types of cells (basically back to the very early embryo state when the original template cells are just beginning to turn into different types of cells.)  Then these stem cells can be grown in the lab and encouraged to become neurons. By imaging these created neurons from people with and without bipolar disorder, researchers have seen a difference in neuron firing between people who respond to lithium treatment vs those who don’t respond to treatment. This hyperexcitability activity of young neurons in bipolar disorder was selectively reversed by lithium treatment only in neurons derived from patients who also responded to lithium treatment.

Mitochondria are structures found within all cell types, and they are the organelles that help provide energy for the cells, along with other important functions. Mitochondria contain their own DNA separate from the cell’s nuclear DNA. Mitochondria DNA is mainly inherited from the egg, therefore the maternal side of the family. In one study, in about 80% of the bipolar patients, hippocampal mitochondria were smaller than even the smallest of the control subjects’ mitochondria. The hippocampus is the elongated ridges on the floor of each lateral ventricle of the brain, thought to be the center of emotion, memory, and the autonomic nervous system. Differences in expression of the genes in the mitochondria were also found between subjects and controls. Is it possible then that a greater predisposition to bipolar disorder could be influenced by the maternal family side?

Brain research is complicated because tissue is difficult and dangerous to extract, and studying brain tissue after death doesn’t give us a good picture of cause and effect across the lifetime. In post-morteum brain tissue, abnormalities could be due to a number of different environmental exposures (such as drug treatment) or trauma such as concussions that are difficult to control in living subjects. A model that does not use living subjects is difficult to create.

However,  researchers have been able to use stem cell from patients to create tissue in the lab for study.  They can take stem cells and “engineer” them to create many different types of tissues; in this study they use patients’s stem cells to create neurons. The hyperexcitability of the neurons is one early indicator of bipolar disorder, and this model of iPSCs in this disease might be useful in developing new therapies and drugs aimed at its clinical treatment.

Here is a link to the study in Nature:

https://www.ncbi.nlm.nih.gov/pubmed/28242870

And a link to one of the earlier studies:

https://www.nature.com/nature/journal/v527/n7576/full/nature15526.html

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C4 and Schizophrenia

When I hear “C4” I immediately think of the television series “Lost” and explosive material. C4 is also the shortened name of Complement component 4- one of a group of proteins that work together to make the immune system.  The C4 gene that codes for this protein is on Chromosome 6, and everyone has different variations in this gene, referred to alleles. Researchers from the Broad Institute, Harvard Medical School and Boston Children’s Hospital, recently published a study with a hypothesis that a key cause of schizophrenia involves different alleles of this gene. The researchers noted that people who had schizophrenia were more likely to have a certain variation that promotes neural “pruning.”

Pruning is part of normal brain development during childhood, and especially during adolescence. Pruning is the process where synapses in the brain are eliminated. It is believed that the purpose of synaptic pruning is to remove unnecessary neuronal structures from the brain; as the human brain develops, the need to understand more complex structures becomes much more pertinent, and simpler associations formed at childhood are thought to be replaced by complex structures.

It may be that different alleles cause different amounts of pruning. Perhaps less pruning, which could lead to too much information being retained, could be a risk factor for mental health.  This could be one of the factors contributing to schizophrenia- there are likely many genetic and environmental factors. More knowledge of these mechanisms may be helpful in creating or refining treatment.

Here is the link to the study’s abstract:

http://www.nature.com/nature/journal/v530/n7589/full/nature16549.html#access

Business Insider’s Discussion of Direct-to-Consumer Genetic Testing (with some quotes from yours truly)

I was interviewed for Business Insider Magazine regarding Kailos direct to consumer genetic tests. I think Lydia did a nice job discussing the benefits and limitations of at home genetic testing.genes

Here’s her article:

I shipped my spit to a genetics company to have it tested, 23andMe style — here’s what I found out

That information can be used for everything from finding out where your family came from to figuring out if you’re predisposed to certain diseases.

Companies like AncestryDNA and23andMe have been partnering with drug companies to try and figure out what role genetics plays in getting sick, and how it can help us get better faster.

But how much can the average consumer learn from his or her genes?

I decided to try out some tests from Kailos Genetics, a genetic-testing company based in Huntsville, Alabama, to find out. All of the tests Kailos offers are designed to help determine how you might respond to certain medications. These include antidepressants, contraceptives, breast-cancer medication, pain-management treatments, blood thinners, and stomach-acid reducers. You can also opt for an all-inclusive test that includes all of these genetic markers.

About me: I’m a 22-year-old woman who is, apart from some seasonal allergies, healthy. I ordered the contraceptives and antidepressant tests that Kailos offers, since those would be the types of medications I’d be most likely to use at this point in my life. I also have a family history of blood-clot problems, which in some cases can be worsened by oral contraceptives.

Here’s how it went down:

Sending my spit to Kailos

A week after ordering the two tests, I got a big purple envelope in the mail:

praxis envelope cropLydia Ramsey/Business Insider

The kit came with instructions, a letter explaining the test, two swabs, a collection bag, and an envelope:

kailos kitLydia Ramsey/Business Insider

I opened up the first swab and started collecting samples of my cheek tissue on the left side of my mouth. To get a good sample, I had to scrape the side of my cheek up and down with the swab for about 30 seconds.

IMG_4990Lydia Ramsey/Business Insider

After repeating the process with the other swab, I put both of them back in the collection bag, packed them all up in the return envelope, and shipped it off to Kailos for testing:

IMG_4992Lydia Ramsey/Business Insider

The results

Once Kailos’ diagnostic lab got my envelope, my sample went through an enrichment process to separate the genetic material — my DNA — from the rest of the stuff on the cotton swab so they can have a better look. Then, the lab technicians looked at my DNA and used a computer to home in on the genetic regions that are relevant to the specific test they were running.

Next, they turned the results over to Kailos’ in-house physicians to interpret the results. These doctors are what allow Kailos to sidestep the problem of needing a middleman — who’d most likely be my primary-care doctor — to discuss my results with me.

Instead of talking to a doctor, my results were posted online to my account on Kailos’ website, which I’d created to order the test.

Thumbs-up for medication No. 1

Screen Shot 2015 10 01 at 4.37.12 PMLydia Ramsey/Business Insider

For the first part of my results, which looked at whether I should avoid certain contraceptives, I saw two big “thumbs-up” symbols.

This meant that the test, which looked at two genes related to how my blood clots, found they were functioning normally — there was no reason they could see that I shouldn’t take the medication.

Those genes were my Factor 2 and Factor 5 genes. Research has found that people with a specific mutation, or tweak, on either of these genes can be at risk of dangerous blood clots, which can stop the blood from flowing from your heart to other parts of your body.

All of this is important for someone considering using contraceptives, since the kind that are taken orally (aka many traditional birth-control pills) can be linked with an increased risk of blood clots in some people; the hormone estrogen in the pills increases certain proteins in the blood that help it stick together and clot.

Thumbs-up for medication No. 1 … sort of

Screen Shot 2015 10 08 at 4.44.21 PMLydia Ramsey/Business Insider

The next part of my test results focused on whether I had genetic tweaks that could make it a bad idea for me to take antidepressants. The test looked at potential indications against taking three of the most popular types: tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), and serotonin-norepinephrine reuptake inhibitors (SNRIs).

Genetics can give us clues about how good our body is at absorbing certain oral antidepressant medications. The CYP2D6 and CYP2C19 genes, for example, make proteins in the liver that break down a hefty proportion of prescription drugs, including antidepressants.

The good news? I should be good to go with all three types: I don’t have any mutations that would cause my body to absorb the drugs poorly.

But while my results suggested my body could handle any of these medications — should a psychiatrist or mental-health professional prescribe them to me, of course — experts say the results aren’t so clear.

Carmela Thompson, a genetic counselor with Genetic Discovery SF, told Business Insider that although she thinks genetic tests are great for figuring out if a person has a hereditary condition like Huntington’s disease, she wouldn’t recommend using them as the sole way to determine the best solution to treating psychiatric conditions.

At least not yet.

“As far as psychiatric conditions go, we’re not there yet and we may never be there,” said Thompson. That’s because the conditions often have multiple factors in addition to genes at play, like environmental factors, so what’s influenced by genetics isn’t quite as clear.

Why Kailos didn’t run into the same problem as 23andMe

Genetic testing companies, like 23andMe, have run into trouble with the FDA for not getting its approval before making their genetic-health tests, which are pretty similar to the ones Kailos offers, available.

But Kailos is already government regulated. As a Clinical Laboratory Improvement Amendments-regulated industry, Kailos’ lab facilities are regularly inspected by the Centers for Medicare and Medicaid Services, which is in charge of ensuring they’re up to par.

Also, having a physician analyze the tests on Kailos’ end is a key way to steer clear of the roadblocks other genetic-testing companies face. Instead of providing uninterpreted information directly to a consumer, that information is going through a trained professional who can make sure it’s interpreted accurately. Troy Moore, Kailos’ chief scientific officer, told Business Insider the reason they opted for more specific tests for certain medications came from their background as a clinical lab.

The verdict

While it was easy to submit my samples and see my results, I didn’t find the test incredibly helpful. I’m grateful to see my results were positive, but part of me was hoping to learn something more nuanced about how my genetics interacted with medicine, like if a certain type of contraceptive would have less negative side effects or would work better for me than another, or if I shouldn’t take contraceptives at all.

Along with the thumbs-up/thumbs-down rankings, Kailos also provides all the raw information for the genes each test looked at, which could help a doctor dive deeper into what the test means for me.

I could have asked a doctor to go over my results with me typically the tests Kailos provides are coordinated with a physician, but when I saw the thumbs-up signs, I didn’t think going over my results with a doctor was necessary.

Which brings up a potential concern when it comes to consumer tests overall: What if, after receiving his or her results, a patient who was on medication chose to use them to start making changes to when and how he or she takes it?

This was a concern Thompson brought up when I told her I hadn’t contacted my doctor about my results. Because parts of genetic tests can get really complex, it’s helpful to have people with at least a physician-level knowledge of genetics around to interpret what it all means, she said.

“It’s just a tool,” Thompson added.

Show Me the Money: A Cynical Look at Gene Testing

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(note: while this post is somewhat cynical, usually I have a favorable opinion of humans in general)

Recently, an associate asked me about the new “suicide gene” discovered this summer. Johns Hopkins published a study that showed an increase in a variation of a protein produced by gene SKA2 in the brains of people who have committed suicide. They then screened a group of people and correlated the level of SKA2 in their blood and their risk for suicide. From this they then designed a model analysis that predicted which of the participants were experiencing suicidal thoughts or had attempted suicide with 80 percent certainty. Those with more severe risk of suicide were predicted with 90 percent accuracy.

Some of my associate’s colleagues had asked about testing for this gene. I told her my hunch would be “more research is needed” before a company could make a diagnostic test with this info.

There sure is an incentive for the drug companies to develop a test. There is an association between anti-depressant use and suicide. As 11% of the U.S. population over the age of 12 years is on anti-depressants, drug companies could make argue that a drug is safer in combination with a test to determine which of the 11% will attempt suicide. And it could save them money in future lawsuits.

There sure is an incentive for genetic testing labs to develop a test. There are approximately 313 million people in U.S. as of 2013. Children under the age of 12 are not tracked statistically, but about 24% are under age 18, so let’s say there are about 238 million over 18. Of that, 26 million are taking anti-depressants. A genetic screening test for 26 million would be a bonanza for the genetic testing companies, even if they are only testing a subset of that population, such as everyone taking Prozac.

However, approximately 750,000 people attempt suicide and approximately 30,000 people commit suicide in the U.S. each year. The main cause is thought to be untreated depression. So the challenge would be how to find the untreated people, and screen them. Hmmm. And if most of the people committing suicide are untreated, would it make more sense to spend money trying to get these people into treatment?
That could ultimately make money for the drug companies and genetic labs, because more people would be prescribed drugs and tested.

My feeling is; if some corporation can find out a way to make money, we’ll see some decrease in the suicide rate, harsh as that may sound.

As far as the genetics of mental health conditions, it’s been thought for a while that multiple genes contribute a small amount each to the overall condition. Most of the recent “suicide gene” studies look at only one gene- for example BDNF was described in Oct 2011, RGS2 was described in Oct 2011 and SKA2 was described in July 2014. A test will most likely need to include multiple genes, which can make interpretation difficult. Sundance Diagnostics claimed they would have a test for suicide risk for those taking Prozac and Zoloft available in early 2014. It’s almost 2015 and the test is not available yet.
Johns Hopkins is looking for partners to help “develop & commercialize the technology as a suicide risk diagnostic test.”
It will be interesting to see who makes it first to market.

link to Johns Hopkins SKA2 study:
http://ajp.psychiatryonline.org/article.aspx?articleID=1892819
Jerry Guintivano, Tori Brown, Alison Newcomer, Marcus Jones, Olivia Cox, Brion S. Maher, William W. Eaton, Jennifer L. Payne, Holly C. Wilcox, Zachary A. Kaminsky. Identification and Replication of a Combined Epigenetic and Genetic Biomarker Predicting Suicide and Suicidal Behaviors. American Journal of Psychiatry, 2014; DOI: 10.1176/appi.ajp.2014.14010008

If you want to partner with Johns Hopkins:
http://www.jhttonline.jhu.edu/TechnologyDetail.aspx?TechID=CE1227A3-B0EE-47FA-A06C-32F7B1CD5563&JHURef=C12394

“Schizophrenia” might include eight genetically distinct conditions

A study from the Washington University School of Medicine reports that Schizophrenia could be a catch phrase for eight genetically distinct conditions. This makes some logical sense as symptoms and drug response vary for people with schizophrenia. People rarely fit into discrete categories.

We know that these are not single gene conditions. This research looks at how multiple genes can work together. Someday it might help with a genetic risk profile.

Go to news.wustl.eustl.edu/news/pages/27358.aspx for more info. I’ll post a link to the abstract when I’m back home and at a better computer.

The Biggest Loser and the Anniversary of Karen Carpenter’s Death.

Karen_Carpenter

Feb. 4th, 2014 was the 31st anniversary of Karen Carpenter’s death. Karen was a drummer and singer, famous for her work with her brother in their duo, The Carpenters. Karen suffered from anorexia and died of heart complications related to the disease. She was only 32 years old.

Feb 4th, 2014 is also the day that the Biggest Loser competition crowned their current season’s winner, Rachel Frederickson. Rachel started the competition at 260 lbs, and lost 155 lbs, -almost 60% of her body weight.  At 105 lbs, Rachel is under the recommended BMI for her age and height.  A trip on the stairs while she walked to the scale was prehaps an indication of her fragile state.

Rachel was quoted on 2/5/14: “I’m at the maintenance point now so I need to find some balance and make sure I work out and I eat healthy and make good choices 90 percent of the time,” she told TODAY after the finale. “I’m not sure (I’ll maintain this weight), but I plan to try new exercises and just continue on this path and see where that takes me.”

While she may have just lost weight for the competition, everyone knows the real challenge begins after the show is over. For some, it’s keeping the weight off, for others, it might be coping with a new-found eating disorder.

Eating disorders have a genetic component, most likely involved with neurotransmitter pathways- pathways which help the brain sooth the body and reward survival behavior (sex, eating, exercise). People with disruptions in the neurotransmitter pathways often subconsciously look for external reward methods- drugs, alcohol, food, extreme exercise, or adrenaline producing behavior. People with eating disorders are often found to be competitive perfectionists. While Rachel may just have lost the extreme amount to win, who knows what hurdles she may now face without the reward of the competition.

While it is a coincidence that Rachel won with an anorexic body type on the 31st anniversary of Karen Carpenter’s death, let’s hope we’ve actually learned something from Karen’s life, and have an open conversation with Rachel about the potential trap. This is an extremely bad example for people who are trying to make a healthy change in their lives, and the Biggest Loser needs to step up and make some changes in the show’s rules to prevent this from happening again.

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23andMe Ordered by FDA to Stop Marketing Genetic Tests

freeimage-6744613-web genome

I’ve been on the fence about 23andMe’s personalized genetic tests.I like that it’s a cheap way to access your own DNA- which many of us may never have the opportunity to do. On the other hand, many of the gene allele interpretations are based on very small research studies that may not apply to the general population. The test has risk predictors for mental health conditions like schizophrenia, bipolar disorder, depression and alcholism. I have looked at the studies that 23andMe bases their intrepretations on, and I find them lacking. I would not recommend that anyone make decisions on treatment, medication, or personal life decisions such as having children, on such results.

23andMe is backed by Google, so obviously there is a lot of money behind the company. I think it is very important that the FDA takes this stand, and demonstrates to the American public that profit has to take a backseat to safety.

Alberto Gutierrez, director of the FDA’s Center for Devices and Radiological Health, said in a letter to the company made public on Monday that 23andMe had failed to address concerns raised on multiple occasions since the agency began working with it on compliance in July 2009. He commented that the the FDA does not have any assurance that the firm has analytically or clinically validated the tests for its intended uses.

23andMe responded  “We recognize that we have not met the FDA’s expectations regarding timeline and communication regarding our submission,” the company said in a statement. “Our relationship with the FDA is extremely important to us and we are committed to fully engaging with them to address their concerns.”

23andMe has plans to start markeing to the public via televison. As far as I can see from the report, they will not be able to do this immediately.

Here is a link to more information:

http://www.theguardian.com/science/2013/nov/25/genetics-23andme-fda-marketing-pgs-screening