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

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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.

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

 

New Clues to the Cause of Schizophrenia

nerve-6

A research study published Aug 25th on Nature Genetics online has found 22 genetic risk loci for schizophrenia, 13 of which are new discoveries. Genes at these loci suggest involvement of two pathways- the calcium signaling pathway and the “micro-RNA 137” pathway. Calcium plays a major role in normal cell functioning. It is a signaling molecular involved in synaptic activity (the junction between nerve cells where neurotransmitters like serotonin are released), cell to cell communication and cell adhesion. In the brain, calcium is fundamental in the control of synaptic activity and memory formation. Calcium signaling disturbances are already known to be involved in different brain diseases such as Alzheimer’s, Parkinson’s, and Huntington’s diseases. The Micro-RNA 137 pathway is involved in neuronal development. This association of development and regulation of brain nerve cell genes with schizophrenia may further understanding and help with new treatments for the disease.

The lead author of the study, Patrick F. Sullivan, MD , commented:

“This study gives us the clearest picture to date of two different pathways that might be going wrong in people with schizophrenia,” Sullivan said. “Now we need to concentrate our research very urgently on these two pathways in our quest to understand what causes this disabling mental illness.”

The link to the study is here:

http://www.nature.com/ng/journal/vaop/ncurrent/full/ng.2742.html

Can We Predict Who Will Attempt Suicide?

suicide

 

Scientists at the Indiana University School of Medicine are looking to answer this question by analyzing proteins in the blood of patients who have mood disorders such as bipolar disorder and schizophrenia/schizoaffective disorder.  They looked at the amount of these proteins in the blood when the person was in a suicidal state vs. a non-suicidal state. A significant difference in expression was found for proteins coded for by the genes SAT1, PTEN, MARCKS and MAP3K3.  SAT1 is involved in the Omega-3 signaling pathway. MARCKS is involved in sleep–wake cycles, as well as mood regulation. PTEN is involved in regulation of the cell cycle and MAP3K3 directly regulates the stress-activated protein kinase SAPK.

Their conclusion was that “suicidality may be underlined, at least in part, by biological mechanisms related to stress, inflammation and apoptosis.” Apoptosis is the natural programmed cycle of cell death. The researchers wrote “our results have implications for the understanding of suicide, as well as for the development of objective laboratory tests and tools to track suicidal risk and response to treatment.” At some point this information could be used to predict and differentiate future and past hospitalizations due to suicidality in patients with bipolar disorder and psychosis (schizophrenia/schizoaffective disorder).

 

The link to the complete article is here:

http://www.nature.com/mp/journal/vaop/ncurrent/full/mp201395a.html

Potential Genetic Testing For Schizophrenia

microarray

A type of genetic testing may be useful for detecting schizophrenia.  A study published July 14th in the journal Human Molecular Genetics demonstrated a significance difference between the number of rare copy variants (CNVs) in patients with schizophrenia vs. the general population.  CNVs are duplications or deletions of small parts of the genome.  The  test for them, called a microarray, has only been around for about 10 years,and is becoming standard of care for people with autism and intellectual disabilities.. This study found a CNV detection rate of about 1 in 13 patients with schizophrenia- about 8%, which is a similar detection rate to some clinical CNV studies on autism.

The study excluded deletions in chromosome area 22q11.2, which are already known to be associated with condition that can include schizophrenia, birth defects and intellectual disabilities. The patients in this study had no obvious physical or mental disabilities.

This is the first study to implicate the area 2q13  as having a significant risk for schizophrenia. Information gained from further study of CNVs may help with medical and/or psychiatric management. This information can be used right now to help families understand reproductive implications for siblings and patients themselves.

Here is the link to the abstract:

http://www.ncbi.nlm.nih.gov/pubmed/23813976

Genetic Link to Schizophrenia?

cnv2

Raising kids has got to be hard enough, but throw in some early warning signs of autism or schizophrenia…and parents are going to need backup.  As we saw with January Schofield’s situation, determining an appropriate diagnosis can be difficult, and can delay treatment and interventions.

In the future, it might be possible to include genetic testing in diagnosis of early onset neurodevelopment disorders.

A study published May 21st, 2013 reports a high rate of disease-related copy number variations in people with childhood onset schizophrenia, as compared to their healthy siblings. Copy number variations are increases or decreases in the number of chromosome material (typically humans have 2 copies of everything, a variation could be an extra chromosome, like number 21 in Down Syndrome, or an extra or missing section of a chromosome.) This study looks at 46 rare CNVs and shows a higher association of people with neurodevelopment disorders who have these CNVs versus their unaffected siblings who do not.

General populations studies are needed to determine the frequency of these CNVs. As testing pricing drops, studies like these become feasible.  Stay tuned.

Link to study:

http://www.nature.com/mp/journal/vaop/ncurrent/full/mp201359a.html