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Tag: schizophrenia

Is Air Pollution Exposure In Childhood Linked To Schizophrenia?

Research has shown that pollution affects physical health, but does air pollution also affect our psychological health? A study, which combines genetic data from iPSYCH with air pollution data from the Department of Environmental Science, reveals that children who are exposed to a high level of air pollution while growing up have an increased risk of developing schizophrenia.

“The study shows that the higher the level of air pollution, the higher the risk of schizophrenia. For each 10 ?g/m3 (concentration of air pollution per cubic metre) increase in the daily average, the risk of schizophrenia increases by approximately twenty per cent. Children who are exposed to an average daily level above 25 ?g/m3 have an approx. sixty per cent greater risk of developing schizophrenia compared to those who are exposed to less than 10 ?g/m3,” explains Senior Researcher Henriette Thisted Horsdal, who is behind the study.

To put this research into perspective, the lifetime risk of developing schizophrenia is approximately two percent, which is equal to two out of a hundred people developing schizophrenia in one’s life. For people exposed to the lowest level of air pollution, the lifetime risk is just under two percent. The lifetime risk for people exposed to the highest level of air pollution is approximately three percent.

“The risk of developing schizophrenia is also higher if you have a higher genetic liability for the disease. Our data shows that these associations are independent of each other. The association between air pollution and schizophrenia cannot be explained by a higher genetic liability in people who grow up in areas with high levels of air pollution,” says Henriette Thisted Horsdal about the study, which is the first of its kind to combine air pollution and genetics in relation to the risk of developing schizophrenia.

The study included 23,355 people in total. Out of those people, 3,531 developed schizophrenia. Through the results of this research one can see that there is an increased risk of schizophrenia when the level of air pollution during childhood increases; however, the researches cannot comment on the cause. Instead, the researched emphasize that further studies are needed before they can identify the cause of this association.

Schizophrenia is thought to mainly be a result of genetics, brain chemistry, substance use, and exposure to viruses or malnutrition before birth. So, I think it is very interesting that exposure to air pollution during childhood may be a cause as well. Additionally, I hope that these findings and further studies become very useful to schizophrenia research and prevention, as schizophrenia is a very serious mental illness and there is no cure.


Planet of the (CRISPR-Edited, Cloned) Apes

Several months ago, scientists in China cloned five gene-edited macaque monkeys. The clones were made through the somatic cell nuclear transfer method (SCNT)—a process in which a viable embryo is created from a body cell and an egg cell—that was used to produce the first primate clones around a year ago. In this instance, however, the monkeys’ genomes were first edited using CRISPR-Cas9—a unique genome editing tool that enables geneticists to edit parts of the genome by removing, adding, or altering sections of the DNA sequence—to show symptoms of sleep disorders by eliminating BMAL1, one of the positive elements in the mammalian auto-regulatory TTFL, which is responsible for generating molecular circadian rhythms. The result? The monkeys exhibited a wide range of circadian disorder phenotypes, including elevated night-time locomotive activities, reduced sleep time, reduced circadian cycling of blood hormones, increased anxiety and depression, and other schizophrenia-like behaviors. 

File:Macaque Monkey (16787053847).jpg

Macaque Monkey

Naturally, the results of the investigation triggered much backlash. According to Carolyn Neuhaus of The Hastings Center, the researchers viewed the suffering of the monkeys as a triumph, and failed to consider the moral implications of their investigation. “It’s very clear that these monkeys are seen as tools,” she told Gizmodo, the latter publication writing in a similar sentiment, “Their experiment is a minefield of ethical quandaries—and makes you wonder whether the potential benefits to science are enough to warrant all of the harm to these monkeys”. 

Nevertheless, the researchers involved in the experiment remain firm in their support of the experiment—the goal of which was to produce genetically identical monkey models of disease for biomedical research—on both moral and scientific grounds. “We believe that this approach of cloning gene-edited monkeys could be used to generate a variety of monkey models for gene-based diseases, including many brain diseases, as well as immune and metabolic disorders and cancer,” stated Qiang Sun, one of the research paper’s authors and director of the Nonhuman Primate Research Facility at the Chinese Academy of Science’s Institute of Neuroscience in Shanghai. Moreover, Reuters reported, “Xinhua [the state news agency] said the program, supervised by the institute’s ethics panel, was in line with international ethical standards for animal research”. Time will tell, ultimately, if the results of their experiment prove consequential on a larger scale. 

Brain Scans Suggesting Schizophrenia?

Schizophrenia is a mental disorder that usually starts between ages of 16 and 30. The symptoms vary from individual to individual, but common symptoms include hallucinations, delusions, and distorted perception. It is suspected usually in teens that have anxiety, depression, or sleep problems. However those symptoms do not always mean this teen has or will develop schizophrenia, usually only about ⅓ of these teens actually develop schizophrenia.

Researches now may have found a special “fingerprint” for the brain to determine if schizophrenia is likely before symptoms emerge. This “fingerprint” is really folds found within the brain. The method looks at MRI scans of the brain and the correlation between the amounts of folds in certain areas, reflecting the strength of connections in these areas. Researches composed an experiment to see how effective this method was at determining one’s likelihood of developing schizophrenia.

Photo Credit: Jurgitta (

The research team collected MRI scans from a group of people in Switzerland, averaging the age of 24. The participants in this study included 79 people with suggestive symptoms of developing schizophrenia and 44 healthy control individuals. The researchers followed all of the participants for four years and found that 16 people in the high-risk group developed schizophrenia. After looking back through the brain scans, the researchers found that 80% of the time, the relationship between the folding patterns of the brain and the individuals who developed schizophrenia correlated. The individuals that developed schizophrenia brain scans seemed to have a “disorganized brain network”, meaning the folds of their cortical regions didn’t go hand in hand as much as the folds in the controls and the high-risk people who didn’t develop the illness. (The cortical regions of the brain refer to the cerebral cortex).

Although not yet perfected, this technique could be very useful in determining out of the individuals who have schizophrenia symptoms, their likelihood of actually developing this disorder.

Lead Leads to Neurotoxitity

Have you ever heard of using bottled water to shower? Sounds ridiculous right, but the people of Flint, Michigan need to do this to save their lives. The city of Flint switched their water supply from Lake Huron to the Flint River in April 2014. The river was later discovered to be contaminated. Since the changeover, scientists have linked the high lead levels in children’s blood to the contaminated water. This is a serious problem.

Lead is a highly toxic substance that permanently affects humans’ brains by killing nerve cells. Not only does lead harm kids’ brain processes, it also may cause various future mental diseases, such as Alzheimer’s disease and Schizophrenia. Throughout U.S. history, people have been exposed to lead poisoning through basic everyday mediums, such as paint, water (from lead-contaminated water pipes), and dust. Children who eat paint chips or lick their fingers after coming in contact with products that have a lead component are poisoning themselves. The lead enters into the bloodstream and travels throughout the body, stealthily making itself at home, poisoning the body.

So how does lead poisoning work? Basically, lead disguises itself as zinc. Zinc is needed to anchor proteins that switch genes on and off. When zinc is replaced with lead, the switches cannot function properly, eventually leading to mental diseases.

Lead Poisoning

Scientists have been researching the possibility that lead is transferable in DNA to offspring. This could be devastating to a population of a town like Flint, Michigan, where the mothers who have lead poisoning could pass this on to their babies. The worst part is that there is no cure for lead poisoning.

Because of the devastating effects of lead in bloodstream, governments have debated the topic of legalizing contaminated water as a bioweapon, using lead as the contaminant. Governments in the past have used poisoned water as an assassination method, proving the effectiveness of this strategy.

Preventing lead exposure and poisoning is critical for children’s health and for future generations.


Source Article

For more info on the biowarfare, click here.

Genetics and Mental Illness

Brain Lobes

Scientists have tirelessly searched through the genetic makeup of people with metal illnesses trying to find a common variation(s) that could account for conditions such as schizophrenia and bipolar disorder. However this has been inconclusive so researchers have turned to epigenetics, the study of how experience and environment effect the expression of certain genes. Epigenetic marks regulate when and how much protein is made with out actually altering the DNA itself. It is believed that these “marks” can affect behavior, and thus may interfere with metal health. This idea was tested in a study with rats.  Researchers proved that affectionate mothering alters the expression of genes, allowing them to dampen their physiological response to stress, which was then passed on to the next generation. This is thought to be similar in humans and these markers develop as an animal adapts to its environment.  Epigenetic research led scientists to prove that offspring of parents who experienced famine are at a higher risk for developing schizophrenia. Additionally, some people who have autism, epigenetic markers had silenced the gene which helps produce the hormone oxytocin which helps the brain’s social circuit. And therefore a brain that lacks this hormone would most likely struggle in social situations. Thomas Lehner of genomics research at the National Institute of Mental Health says that studies and research have shown that epigenetic modifications impact behavior and he also believes that these effects can be reversed. By studying genes at the “epi” level, researchers are hoping to find patterns that were hidden at the gene level.  Finding and targeting these patterns can lead to more effective treatment of and management of certain mental illnesses. There are many projects and studies at some of the most prestigious institutes, such as Tufts and Johns Hopkins, that are focused on the study of things at the epigenetic level.

Original Article

Further Information:

Epigenetic Markers and Heredity

Epigentetics and Autism 

Genetics and the Brain





The New Source of Mental Illness

a three dimensional recreation of DNA methylation

a three dimensional recreation of DNA methylation

For years scientists were convinced that the root cause of diseases such as bipolar disorder and schizophrenia lay somewhere hidden in the human genome. But the particular genetic sequence that would supposedly be linked to these illnesses remained elusive.  So researches turned to the developing theory of Epigenetics.  Studies from King’s College in London and related in this article have shown that Epigenetic (changes in gene activity caused by the environment) changes might be responsible for bipolar disorder and schizophrenia.  Jonathan Mill and colleagues scanned the genome of 22 pairs of identical twins.  For each pair of twins, one of the twins was diagnosed with either bipolar disorder or schizophrenia. With the understanding that chemical methyl groups attached to particular sites on a genome are responsible for the “turning of” and “turning on” of genes, Mill and his team “scanned for differences in the attachment of methyl groups at 27,000 sites in the genome.”  The researches found variations in the amount of methylation of up to 20 percent in the gene ST6GALNAC1 (which has been connected with schizophrenia) and differences in the amount of methylation of up to 25% in the gene GPR24 (which had previously been linked to bipolar disorder).  Interestingly Mill’s team found that “a gene called ZNF659, showed over methylation in people with schizophrenia and under-methylation in those who were bipolar, suggesting that the conditions might result from opposing gene activity.  These findings certainly support the theory of Epigenetic’s being a real factor in behavior and mental illness.  They also serve to confirm that bipolar disorder and schizophrenia are related disorders.  This relates to our unit in the sense that Epigenetics deals with the expression of the DNA and genetic sequence we are learning about.  While we read about how the nucleotides are sequenced, Epigenetics could potentially be responsible for how DNA is expressed.

Related reading:

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