Saturday, February 15, 2014

Gene-Environment

TAG of the Week:


Here are the link and questions that follow, for the blog next week- 

Read this new article titled "USC Scientists Show Gene-Environment Interaction Augments Risk for Developing Autism"

After reading "Challenges and opportunities in genome-wide environmental
interaction (GWEI) studies" by Hugues et al and the news article above, briefly describe some of the strengths and limitations and future applications of Gene-Environment Interaction Studies.

OR
1. You can share the new, 'surprising' information you learned
2. Ask a question that needs additional clarification, 
3. Share a news link relevant to the discussion.  
4. Reply to another student's comment.


41 comments:

  1. I found the above news article discussing the interaction of the MET variant and air pollution extremely interesting. So, I managed to find another related story surrounding the discovery of additional gene variants (copy-number variants) also related to the development of ASD. When reading these articles, I noticed that both authors stated that the genetic variants that may prove to be predictive markers are not universal and are only present in a small portion of those with ASD. When thinking about ASD from a sufficient cause/causal pie model, I think we are well on our way to determining new component causes beyond the already identified gene variants, air pollution, etc. and I strongly believe GWEI will play an important role in discovering how these factors interact to result in disease. However, as the Hugues et al article noted, in regards to GWEI studies that do find significant interactions between genetic variants and environmental factors, the replication of these findings will prove to be difficult. And as Kendra already stated, there may be problems classifying these exposures across different studies and populations. Although GWEI studies are providing us with a new way to look and learn about certain conditions, I do think we need to keep in mind that they are not infallible.

    Source: http://www.sciencedaily.com/releases/2013/01/130114172010.htm

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  2. I agree that the efforts and findings of genome-wide environment interaction (GWEI) studies are very important and helpful for finding the etiology of different diseases. As Hugues et al wrote, these type of studies are beneficial for determining etiology of common multi factorial diseases where the mechanism of the identified genetic variants is not clear. For this reason, it seems that a disorder such as autism would be the perfect choice to study in this way. However, I think that performing GWEI studies on autism spectrum disorder might be more difficult and more subject to errors with confounding and population missclassification than with other disorders. The disorder exists on a spectrum, and so individuals on one end might have a very different phenotype and even genotype than another. It exists in several different ways and so the results of a gene-environment interaction might not be representative of risk for everyone as the USC article suggests. For example, the link between air pollution and genetic risk of developing autism spectrum disorder might only excuse for individuals with a low level version of the disorder and not correlate to everyone else. The gene-environment interaction for other versions of the disorder might be completely different. I think this type of issue that makes GWEIs controversial and hard to replicate, because any results may not be universal.

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  3. Gene-environmental interaction studies offer an exciting future in the world of medical research. The article linked above explained that recent research has found that air pollution might increase the risk of autism in people who already have a genetic predisposition for autism. Along the same lines, an article published just last month reported on a study that found that pesticide DDT exposure increased the risk of Alzheimer's disease in people who already had a genetic predisposition for the disease. I found this interesting because both autism and Alzheimer's disease have largely been a mystery to the medical community. It is only in recent years that researchers have been able to discover more about the two conditions' etiology. As of right now, neither have a cure and very little is known about how to prevent either of them. However, these recent gene-environmental interaction studies offer greater insight into the two conditions. While much more research will need to be done to confirm those two studies, it is still a hopeful development. It will be exciting to see where this research leads in the future.

    http://www.livescience.com/42874-alzheimers-disease-ddt.html

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  4. Wow! I definitely found the news article on "USC Scientists Show Gene-Environment Interaction Augments Risk for Developing Autism" is be very interesting and shocking. The United States Environmental Protection Agency reports that the most commonly found air pollutants are particulate matter, ground-level ozone, carbon monoxide, sulfur oxides, nitrogen oxides, and lead. These pollutants, many coming from automobile and industrial emissions, pose many negative effects on human health. I can not believe they are finally linking Autism rates to genetics and air quality. This finding and continuous GWEI studies and research on the environmental connection with Autism and to other diseases. This information is very important for public health and policies for disease prevention. Also, it just goes to show that environmental health and standards for air quality need to be much more stringent.

    http://www.epa.gov/air/urbanair/

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  5. After reading the article “USC Scientists Show Gene-Environment Interaction Augments Risk for Developing Autism”, I was extremely interested in how your genes can interact with the environment to influence disease. I did not know much about this topic until our guest lecture today in class. Dr. Fabian used the example of the first year medical students and depression, explaining that two students may have the same environmental stressors, but the one with the gene implicating depression is more at risk for developing these symptoms. In this way, two children could be exposed to the same air pollution levels, but the child with the MET gene variant is more likely to have autism. I am very interested in this topic of gene-environment interaction, and I think that there is a lot of opportunity for public health studies and interventions in this field.

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  6. I think the biggest strength of genome-wide environmental interaction studies is that they can show people how the interplay between genes and environments can determine the traits. More people need this knowledge because many falsely believe that diseases are caused by one or the other. For example, in previous years, parents attributed their children's autism to their parenting. In the past, children with autism spectrum disorders were misdiagnosed with schizophrenia and treated with shock therapy. We have since learned that there is a genetic risk of developing these neuropsychological disorders and now focus on behavioral and language therapies for those diagnosed with them. GWEI studies, like this one conducted at USC, can identify for both the public and public health officials, environmental exposures that increase the risk for diseases with known risk genotypes. We can then work to address avoidable exposures, such as lead paint or mercury thermometers, or alleviate more widespread exposures, such as air pollution.
    As the Hughes et al. article mentioned, there are several factors to consider when conducting GWEI studies, such as confounding variables, measurement error, and miscalculation, but I think these are factors to consider when conducting any research. With proper technique, precise implementation, and statistics, these factors can hopefully be controlled for in future GWEI studies.

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  7. This article, along with our class today and the required reading took me back to my HS345 Global Environmental Public Health class. I remember the first week of class we watched a documentary about a woman who believed she got cancer due to lead in the paint around her home. She then went on a journey to find out more about the lead, how toxic it was, and who allowed to be there. This documentary, along with the article about ASD, have made me realize how important the environment is in our understanding of a person's health. I think this topic is interesting. I feel as though my classes either focus totally on the environment or completely on the genes (like my genetics class), so I'm really excited to see the genes and the environment working together in this class.

    Similar to the USC study, I found another GWEI study that I thought was interesting and complementary to what we've been learning about. This discusses a Parkinson's and Environment and Genes study. Scientists found that as exposure to pesticides increased, so did risk for Parkinson's disease. This is interesting because Parkinson's is a disease in which scientists have focused mainly on genetic risks. It has been widely researched from many angles, but I've yet to see anything from this angle of genes interacting with the environment. GWEI studies are advantageous because they describe more pathways toward becoming ill with a disease. By knowing more pathways, scientists have more opportunities to interrupt and try and prevent a disease (coming back to a public health perspective). However, the biggest limitation with GWI studies is that there can be many confounders that affect results and need to be controlled for. This can make a study expensive, and make the data difficult to interpret.

    Article on Parkinson's Environment and Genes study:
    http://www.medscape.com/viewarticle/820257

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  8. I think the article "USC Scientists Show Gene-Environment Interaction Augments Risk for Developing Autism" is a great example of how GWEI applies on the role of environmental factors and disease risk. This air pollution and autism article shows as another stepping stone for us to learn how environmental factors and disease relate and for us to learn more on "understanding that genetics is important in the uptake and metabolism of toxic substances" (Hugues et al). I believe the GWEI studies have great potential in linking disease risks in our genes to what we are exposed to in our lives. If we are to know what disease we are at risk for by looking for it in our genes can greatly help us in fighting or even preventing disease. However, regarding external factors, because there are many, probably even millions of possible factors that we are exposed to, it is extremely hard to distinguish which external factor have affected us. Furthermore, studies that have been done have not come out with equal results.
    Nonetheless, with more research and more studies, we can get get closer to finding what factors contribute to our disease and hopefully find cures to many disease that have yet to have a cure, such as autism.

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  9. A question I have for this study is whether or not pregnant women put their unborn babies at risk by being exposed to air pollution exposure. The end of the article briefly mentions that Campbell and Volk are continuing to study these interactions, but no information is supplied. The interaction between genetics and the environment is important to study in order to gain a more complete understanding of a person's health. I feel as though it is crucial to examine pregnant women in addition to young children so as to fully understand the role genetics plays in Autism Spectrum Disorder.

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  10. A strength of Gene-Environment Interaction studies is that we can learn more about the risk of getting certain diseases when both genes and environment are tested against each other. Like Dr. Fabian mentioned in class when talking about investigating disease and the environment, it's important to think about all risks to a person's health in both the environment including the population's varied genetic make up.

    A limitation of this study specifically is that this is only the result of one study. In order to show reliability of this result this study must be preformed in many populations, environments and geographic locations around the world.

    I hope in the future more epidemiologists and environmental health professionals will continue to explore gene-environment interactions for many diseases. Hopefully if the evidence is strong enough that the environment is acting on genes, public health officials will push for control of these harmful pollutants and environments.

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  11. I find it surprising how this is the "first demonstration of a specific interaction between a well-established genetic risk factor and an environmental factor that independently contribute to autism risk". It is widely believed that gene-environment interactions contribute to increased autism risk, but I thought it was proven beforehand. A lot of health concerns include increasing autism risk, for example parents choosing not to vaccinate their kids out of fear of increasing their risk of autism. I am confused as to why a lot of solutions we have to health concerns always have the risk of autism as a possible side effect. Does everyone have a genetic predisposition to acquire autism, or is the gene too sensitive to any slight stimulation?

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  12. I found today's lecture on Geographic Information Systems (GIS) to be very interesting due to the wide range of applications. While the examples Dr. Fabian gave of how GIS can be used to make maps of geographical objects and used to assess exposures were interesting, I was confused and eager to learn how this method could apply to genetic disorders. It was exciting to see how a GIS model of layering can be used to visualize aspects of the human genome. I also thought that the comment she made about how 'people always believe maps,' was thought provoking because as she explained through the Northampton cancer rates example, there are sometimes other variables that can effect such rates, and the cause of disease is not always what it initially assumed. Therefore, GIS is a very useful tool, but it is best used in conjunction with other data to get the full story.

    I came across this story on NPR about the very recent death of Roger Tomlinson, known to be the 'father of GIS.' The story explains how and why Tomlinson invented GIS in the 1960s, which 'revolutionized industry and government.' It’s definitely worth a quick listen!

    http://www.npr.org/2014/02/13/276522411/tech-innovator-and-master-of-maps-dies-at-80

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  13. I found this article to be very interesting. I also find that it gives me hope that researchers are one step (albeit a small one) closer to fully understanding the complicated disorder that is ASD. That being said, I am still in need of some clarification. The article states air pollution without giving any specifics, like how much or what kind. There are different kinds of air pollution so it would be helpful to know more about that. In addition the study claims, "Our research shows that children with both the risk genotype and exposure to high air pollutant levels were at increased risk of autism spectrum disorder compared to those without the risk genotype and lower air pollution exposure." Do the researchers mean to say that children with the risk genotype and high pollution exposure are at increased risk compared to children without the risk genotype and children with lower air pollution exposure, or do they mean increased risk compared to children that do not have the risk genotype and have lower pollution exposure at the same time? I'm just a bit unclear on the wording. It just seems obvious that children with the risk genotype would be at increased risk to ASD no matter what their pollution exposure. Nonetheless this article shows that research is making strides towards understanding Autism Spectrum Disorder.

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  14. I thought that the article was very interesting and reinforced how genome-wide environmental interaction studies can be used to further understand the true impact the environment can have on an individuals overall health and how the risk of a disease can be heavily influenced by the environment they're exposed to. After reading the article it made me realize that initiatives towards regulating air pollution more heavily should be put in place, especially due to it's correlation to ADS. The article made me realize how heavy the impact of ones environment can be on their health and because of this I think there is a lot of potential for GEWI studies in the future.
    I think that one of the drawbacks of this particular study is the fact that this was the first demonstrated linkage between ADS and environmental air pollution. In order for this air pollution to be considered a definite factor for the development of ADS, i believe more studies need to be performed to support the findings in this article. However, it is definitely a start in the right direction towards discovering more gene-environment interactions for many other diseases.

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  15. I thought the article was interesting, but somewhat vague in the type of pollutants that were associated with autism. It is definitely nice to see that progress is being made in investigating the association of environment and genetics though. It says at the end that the investigators are still studying the interaction so it will be interesting to see what else they find out.

    The GWEI paper shows many strengths and weaknesses of the new field looking at genome wide environmental interactions. Strengths include learning how certain environmental factors or pollutants impact genetics and cause certain genes to exhibit certain traits or disorders. Also, if these interactions are proven through studies, it would help environmental health officials to change policy and educate the public to become more aware of pollutants. However, the human genome project was completed in 2001, so many of the genes are still being investigated. Also, GWEI studies are prone to confounding variables as well as being difficult to complete due to the massive sample sizes needed to get statistically significant data.

    Despite the difficulties in conducting these studies, I'm excited to see how these GWEI studies play out in the future because they could potentially find out some exciting gene-environment interactions that could change how certain diseases are treated.

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  16. Genome-wide environmental interaction (GWEI) studies are very interesting. As for their strengths GWEI studies help identify links between genes and environmental factors which can help raise public health awareness to develop preventative measures to eliminate environmental risk factors. In regards to this I found an article linking air pollution with brain cancer in India. This study is still being conducted, however if they find a link between air pollution and brain cancer, researchers would like to find new ways of decreasing air pollution/ increasing air quality in India- (one strength of GWEIs). Although GWEI is ideally a great type of study, it is difficult to conduct and is limited by confounding, misclassification, and miscalculations, which can lead to false associations between genes and environmental factors. Despite these limitations I believe GWEI studies have a promising future after more research is done on how to better conduct these studies.

    Link: http://health.india.com/news/could-air-pollutants-cause-brain-cancer/

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  17. I found the guest lecture on geographic information systems to be extremely interesting. Prior to the lecture I didn't know anything about GIS, how it worked, or that studies were being conducted using this method. This type of mapping seems extremely promising and appears to yield unbiased results, an issue with many other research methods. Not only does this technology gather a great deal of important information pertaining to particular studies, but the layers are also shared in a database for others to use which is a very helpful aspect. Additionally, aside from the research aspect, I found it intriguing since the setup of ArcGIS is similar to that of Photoshop and provides an interesting approach to viewing, layering and manipulating the maps. I really like the GIS approach to research and would love to learn more about this method.

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  18. GWEI seems like given enough time, it could be very beneficial to society. While I have heard of many potential links between autism and other things, the environment had never been one of the those. I'd never considered a link between air quality and autism. I find this discovery very interesting because I could see gene-environment interaction studies expanding and being used to determine causation, or at least association between the environment and genes, for many other diseases. With enough time, we could find associations we weren't even aware existed.

    There will of course be limitations with this. Some scientists may to too quick to associate certain environmental factors with diseases. This could lead to a skeptical population that doesn't act on new recommendations or take recommendations seriously. False associations may change behavior unnecessarily. I think over time though we will find many more associations that we weren't aware were out there.

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  19. Genome-wide environment interaction studies present an interesting path for future genetic research. It is interesting to see how there is shift in genetic research in trying to understand how the biology of one's genes can be augmented by the environment of exposure, just as is presented in the article about autism and air pollution. These studies present opportunities for people to better understand in the future which environmental factors need to be avoided based on their own genetic makeup in order to prevent disease from occurring. Results from these kinds of studies would be powerful because they have the potential to enable people in addressing their health at a whole new level.

    Of course, the newness of genome-wide environment interaction studies pose several limitations. For one, these studies are often seriously underpowered because of small sample sizes and statistical programs have still not been developed to estimate appropriate sample sizes. Furthermore, understanding how to quantify environmental exposure for these studies is difficult, since exposure varies so different from person to person in every day life. While genome-wide environment interaction studies hold potential, more work needs to be done to advance the study methodology behind them.

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  20. I found that article very interesting and hopeful. Autism Spectrum Disorder (ASD) are such a prevalent disorder it seems that almost everyone knows someone who has ASD. Having a better understanding of what can cause or even what is known to be associated with a higher risk of ASD can be important to understanding the disorder. I had not heard of the MET gene before this article so I did not know that any genes had been associated with ASD before. So when I read the article it was even more surprising and interesting to learn that environmental factors have been linked to the ASD as well and that these two factors combine can have an even more increased risk for ASD. ASD is something that has had so much misunderstanding and misinformation for the general public, I am very happy to know that finally trustful information and associations are being found that may hopefully lead to treatment options some day when the disorder is better understood.

    I think there are many strengths to gene-environment interaction studies. Gene-environment interaction studies combine I think very important factors that can influence a disorder. Often times genetic studies don't pay as much attention as they should to known environmental associations. Combining these two important influences and how they interact with each other in relation to a disorder can really give important insight into these disorders. From what we've learned I cannot think of any limitations specific to gene-environmental interaction studies that are not applicable to other types of studies. In general gene-environmental seems like an important step forward for medical research and will probably have a huge impact on public health studies and interventions.

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  21. Gene-environment interaction studies have both strengths and limitations. These studies will identify what effects environmental factors have on genes. This is important because it demonstrates that our physical environmental can cause disease by altering the genes in some way. It is necessary to further investigate how the environment can change gene expression in order to find a way to prevent or treat diseases. In the article posted above, findings suggested that children with the risk genotype who were exposed to high levels of air pollution showed an increased risk for autism. This is an important finding but here is where I think the limitations are evident. Although the findings show that air pollution may contribute to autism in those who have the risk genotype, the study offers no solution to this problem. I cannot see a practical solution to this; not every person has the means to move to a less polluted area if his or her child has the risk genotype. I praise these studies for bringing awareness to how environmental factors contribute to disease; however, more research is needed to bring change. As of right now, these findings only lead to a "so what?" response because I don't see how anyone can change their physical environment in order to lower his or her risk of disease. That's just not practical or realistic!

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  22. This is a very interesting factor to consider. Current knowledge indicates that air pollution is known to contribute to a variety of diseases or conditions. Especially when it comes to conditions of the lungs, we know that air pollution can exasperate such issues. However, this is different from other physical ailments, as these findings pertain to a neurological disorder in autism. Neurological disorders are most often either hereditary, congenital, or resulting from traumatic events. This finding, considering that known confounders were accounted for, goes to show how the emerging field of epigenetics is presenting its validity. The environment clearly has an effect on the expression of many of our genes, but it is hard to quantify the extent of that effect. If this finding can be replicated in many more studies in the future in various regions, then we may move towards a better route in preventing and or treating autism spectrum disorders.

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    Replies
    1. I agree with you, Alvin. Epigenetics is a field that has shown to help explain external factors as they relate to disease. Our genes respond to external influences significantly. I think that our guest lecturer's , Dr. Fabian, presentation on GIS can help us quantify and track the dynamic relationship between gene expression and diseases. Public Health professionals and physicians can benefit from examining the layers and bridges of our genome and outside world. I think GIS research in epigenetics can help us identify the source of disease and disorders through the visualization of aspects of the human genome, chromosome space, genes, expression levels, conserved regions & genetic susceptibility. In this way, environmental and behavioral factors and GIS research can answer a lot of question in epigenetics. Especially as you mention in explaining disorders.

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  23. Reading this article, I was really very surprised to see such a broad exposure factor to be linked to Autism. I understand Autism to be decently prevalent and rising, but would have expected a more specific risk factor; however, the fact that there is a deeper understanding of the risks for Autism is astounding. Frankly though, I think the strengths for this paper are limited to its implications: that we are beginning to understand Autism and can potentially reduce incidence. Given such hopeful implications, I think the study needs to be scrutinized more than others. With that said, the limitations are that there is both a gradient of air pollution and of Autism; I would expect a dose-response relationship, but such isn't shown. The study (I found it and read it) also states that there was a multiplicative interaction between NO2 and the gene, MET-- I would expect the dose response relationship to at least apply to NO2 and MET. Lastly, I think that the study needs to look further into the families in question. Given that Autism is highly genetic (at least, for what I understand of it), are such families more likely to live in areas of high air pollution than not? Looking at the study, there isn't a shown population analysis, as in whether or not the control and cases differed in any specific characteristics and exposures. I think its important to look at confounding factors, especially in such a controversial concept.

    Also, if anyone finds it worth noting, two of the authors had conflicting interests. Third author Lurmann received support from an air quality violations settlement agreement and first author Volk received travel funds from Autism Speaks to present an academic paper at a conference.

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  24. I find it very interesting and look forward to the development and the advancement of the genome-wide environmental interaction studies (GWEIS). The article “USC scientists show gene-environment interaction augments risk for developing autism” shows how far we have become towards understanding environmental factors and risk factors for diseases. Also, we have built knowledge on how all of this is affecting our genes. People would have never understood the links between pollution and autism a few years ago. However we have advanced and increased our understanding of how genes work, which is truly amazing. It is almost appalling to think about the knowledge we still haven’t discovered yet. Also, it is interesting to know that everyday things like the air you breath in or the food you eat can have such detrimental effect on your genes as well as your future generation. I wonder if there is anything that you can do to prevent this. All we have learned so far is about how the environment or some external factors affect our genes negatively. I wonder if there is anything that contributes positively to our genes and a positive trait that will be passed down to our future generation. There must be an external factor that if exposed, it will give us an immunity in a disease, help us live longer, or something beneficial. I am certain that once we understand more about genes, some of these will be discovered and I am excited for what the future holds for genomics.

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  25. After learning more about epigenetics and discussing how our external factors influence our DNA, the article above seems like a step in the right direction in terms of potentially developing greater awareness for those who are trying to keep their child’s risk of developing autism at a minimum. I believe that there is a great future for genome-wide environmental interaction (GWEI) studies, and that we will be able to learn a lot from the results of these studies. Knowing that autism is a heritable disease in which genetics plays a large role, the increase of awareness for specific environmental factors that lead to the disease will be a useful tool for parents in the prevention of the development of this disease. Even though there has been an association found between air pollution and the genetic risk factor of the MET gene variant, more studies still need to be performed in order to determine the specific mechanisms of how these interactions increase the risk of autism. GWEI studies are producing great results in order to increase our awareness, but if these interactions prove to link to an increased risk of autism, how might communities work to combat the problem of air pollution? How accessible will it be to determine if this genetic variant is present in individuals, and how we can aide in making sure those that are at risk receive the proper tools to decrease their risk?

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  26. I found the article about the link between air pollution and increased risk for autism spectrum disorder very interesting. It made me think about the video "The Ghost in our Genes."

    How exactly does air pollution work to increase the risk for ASD? Is it similar to imprinting, as discussed in the video? Does the increased risk for ASD occur only during pregnancy, or are previously discussed 'sensitive periods' at work to increase the risk of ASD due to any amount of significant exposure to air pollution during the mothers life?

    I also find gene-environment studies to be particularly interesting. However I do question the validity of these studies as of now. I question how researchers are able to pinpoint exactly which factor from the environment affects our genes. I think that to more accurately account for any variances or variables present in the data, gene-environment studies should be conducted as cohort studies to be able to observe any variances in lifestyle. However, overall I still find these studies to be promising.

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  27. This article was very interesting. We hear about how environmental factors affect us in different ways all the time. I think this article further emphasizes the role that the environment plays in our health.

    Juliana asks some questions that I am also curious about, such as how does air pollution increase the risk for ASD? And whether or not there were specific sensitive periods to increase the risk of ASD. They mention that they studied kids from age 2-5 years old, I'm wondering if 2 year olds were more susceptible to the air pollutants when compared with the older kids in the age group? What is the sensitive time period in which if you are exposed to air pollutants and have the MET gene are you more likely to develop autism? That information would be interesting to know and was not specifically stated in the article.

    However, like GWAS studies, I think GWEI studies seem like a good way to obtain more information about a certain area of study. I think they have some limitations, as all studies do, so therefore they can be unreliable and inaccurate. Despite these limitations, they open up opportunities to conduct further research on a topic and give us more information about a certain area.

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  28. For years, we have known that the relationship between our genes and the environment influences our lives. I found the USC study to be fascinating in that it shows a glimpse of what may cause autism. Today, the origin of autism is highly debated, with many people believing that things like vaccines lead to autism in children.

    Future gene-environment interaction studies have the ability to solve the mysteries of where certain diseases and disorders come from. We know that both genetics and environment influence the expression of the genome, so GEI studies seem to be the logical next step in pinpointing what actually causes these disorders.

    However, there are many environmental factors that can be taken into account when conducting a GEI study. The myriad of possible environmental factors and confounding factors will serve as a hurdle for these studies. It is extremely difficult to separate environmental factors in order to have a solid epidemiologic study. The autism article highlights this because although it names a certain environmental factor-pollution, it is unclear what exact type of pollution the study was examining. Where the children exposed to high levels of carbon monoxide, nitrogen oxide,lead, or maybe something else? The study does not specify, and when it comes to examining other environmental factors, it will be difficult for others studies to pinpoint which exposure exactly interacted with the gene.

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  29. I think GWEI studies could be very helpful because we know that there are many risk factors and components that go into diseases. Everything I had ever learned about autism spectrum disorders led me to believe that they relied heavily on genetics or on the risk factors from the parents’ lifestyle. It is interesting to read the USC article and realize that environmental factors can also play a role in autism spectrum disorders. Although the genetic factors are still dominant, environmental factors increase the risk. It makes me wonder how many other diseases could be prevented if environmental risk factors were found and avoided. Instead of just knowing environmental risk factors, GWEI studies can show how the environmental factors react with genetic factors. I hope to see more studies like this in the future and that the environmental risk factors can be controlled and avoided to prevent diseases and disorders like ASD.

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  30. Genome Wide Environmental Interaction studies can be greatly utilized to help us discover possible causes of diseases due to epigentic factors like pollutants and the environment. I felt that it was important that the news article stated that autism spectrum disorder is inheritable, but that having risk alleles and being exposed to pollutants provides a huge risk in offspring developing the condition.
    Of course as with every scientific research method, there are limitations to the study. Even though the study linked environmental factors to helping enable gene expression for autism spectrum disorder, there are possible confounding factors that may have also aided in doing so. As the article had mentioned, autism is an inheritable disease, so the families of the children should be closely examined to determine the child's genetic risk of developing the disease.

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  31. I found the article "USC Scientists Show Gene-Environment Interaction Augments Risk for Developing Autism" quite an interesting read. From what we've learned in class so far, it seems like anything and everything becomes a factor to how our genes are composed. Reading the article makes me wonder what we can do for our environment in order to make it as safe and risk-free of mutated genes as possible. The obvious notion is to just move away from an area that is highly concentrated in air pollution or waste product. But that's only a short-term effect... and a longer-lasting effect is what we are aiming for.

    Back on topic, I found another article that somewhat helps explain the cause of air pollution increasing the chance of autism. The article explains that exposure and inhalation of ultrafine air pollution articles affect the brain significantly. Experiments were conducted on mice revealing that consistent air pollution entering the system damages the brain in all regions, the most notable being the ventricles. Because of the damage, it can lead to higher risks of developing autism and schizophrenia.
    Source: http://www.foxnews.com/health/2014/02/18/air-pollution-exposure-may-increase-risk-neurodevelopmental-disorders/

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  32. I found the article on the linkage between ASD and environmental pollution very interesting, but it seemed to leave me with more questions than answers. As Hugues article states, "Developing methods to overcome the conceptual, technical, and methodological hurdles GWEI studies involve is the focus of much ongoing methodological work." I do think this study does contain some of the challenge/issues that are often associated with GWEI studies. As mentioned by previous students, I was immediately curious as to whether there are sensitive periods that may be pose a greater risk for such pollution-gene interaction. It seemed to me studying children ages 2 to 5 is a large range, considering how different a child at age 2 is in development compared to a child at age 5. Also, as one of my peers mentioned, the confounding factors, such as funding, left me a little questionable as to whether they were putting forth an idea as fact that may still need a lot of research, studying, and specification. In my opinion, the future study mentioned at the end of the article, which they plan to begin on the interaction of air pollution exposure and the MET genotype in mothers during pregnancy, seems to be a study that could reveal much more and have less variables.
    Nonetheless, despite future issues that may arise and need to be resolved from this GWEI study, it is something worth noting and going forward with learning more about. It is evident that breakthroughs are being made through GWEI studies and I am curious to see what the future holds!

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  33. A limitation to GWEI studies is determining the specific environmental exposure that interactions with a gene to cause as disease. In the new article, USC scientists believe that interactions between air-pollutions and the MET gene variant increase the risk for developing autism, where they collected data regarding “past residences of the children and their mothers.” However, multi-exposures and many other factors may be involved in developing the disorder. For example, other factors could include the dietary behaviors of the mother, her stress level during conception, and can even due to the father’s genes. Hence, it is will take a lot of time, research, and money to determine the exact causes of genetic illness.

    Another limitation is how will findings from these studies be implemented for a nation-wide intervention? Suppose that the USC scientists were able to find that air-pollution does in fact correlate to the MET gene variant and autism, how could this information be used to prevent the development of autism? Warn individuals to move from their polluted residency, what if they’re not in any financial situation to move? Advocate and raise awareness about the importance for clean air?—Though getting rid of the pollution will take a lot of time and financial resources.

    A strength to GWEI studies is that if it is successful in determine genetic-environment interactions, at least researchers can begin coming up with interventions to prevent genetic illnesses and possibly the world will see a reduction of genetic diseases. Aschard’s and et al’s study mentioned that there is “increase of advanced molecular genetics techniques” that makes it “possible to investigate the role of environmental factors in disease risk.” Though it may take time, commitment, and money, for potential to eliminate the developing of several genetic illnesses is a great gain for future generations.

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  34. This study seems a bit superficial in its findings. What kinds of air pollutants are they talking about? Smog, coal, power plant, biproducts from chemical plants, nail polish fumes? Honestly that makes me suspicious seeing as any research to do with Autism is extremely important especially when it is now effecting a record amount of children. Air pollution can do a lot of things, ruin our environment, increase risk of cancers or even cause them however I think it is very arbitrary to say that air pollution is a risk for autism. Though it may trigger a gene to turn on associated with autism. GWAS studies are more important so we can identify problem genes and proceed with methods of treatment. Honestly this study seemed like an inefficient use of time. Of course pollutants are bad for you....so is fast food and radiation. Now that we have established that I believe it is a better usage of time for the 1 in 88 children in the US who have it to investigate the genetic factors and specific genes associated with it. Through the genes we can then figure out other minor risk factors associated in the bigger picture. The study looks like it has good intentions but I am truthful in saying it was extremely vague on parameters and other risk factors in their participants lives that could be more pertinent to triggering autism. Finding a cure for any disease is a measure of patience, time, and will, but efficiency and focus is key. Taking a step in the right direction and focusing on what actual genes are involved and how we can manipulate them to end the disorder will be key. Gene environment studies supplement our learning and further our understanding, however this only occurs when they are not vague accounts of possible realities.

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  35. I found a very interesting article that relates to gene-environment interactions with regards to culture and a gene that is associated with depression. The gene is for environmental sensitivity. It is associated with depression because those who are naturally more environmentally sensitive will be more likely to be affected by negative surroundings, thus possibly leading to depression. The gene-environment interaction study was performed on Koreans and Americans, and the subjects were later tested for the gene via blood samples. The results were pretty surprising. The Korean subjects who tested positive for environmental sensitivity were more likely to suppress their emotions. Americans who tested positive for sensitivity actually showed the opposite pattern, expressing their emotions much more. This might be due to the social norms of each country, since Korea is a collectivist East Asian society and America is more individualistic and is a Western society. This is a good example of how cultural differences and norms can influence gene and environment interactions. It would be very interesting to further study not only gene-environment interactions, but genetic, environmental, and cultural interactions and the effects they have on human disease.

    http://psychcentral.com/news/2011/11/09/cultural-differences-impact-gene-environment-interactions/31234.html

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  36. I was surprised to hear about the link between autism and air pollution but the study seems to be very vague about it's objectives, methods, and really any pertinent details that are necessary for presenting a viable study to the public. I feel like we're expected to take their word for it without any evidence or background detail. I also question the generalizability of the study because these children were all recruited from California. It is likely that many of these children have never been outside of the state.

    Also, what kinds of level of air pollution are we talking about? Every area has air pollutants. Some more than others so I think it's important for them to discuss levels of exposure in different areas and specify types of exposure. Air pollutants contribute to a number of illnesses such a asthma. Is there a possible link between asthma and autism rather than autism and air pollution? Could there be confounding factors? I just don't think this article provides enough information.

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  37. I too was not particularly surprised by this article. Though I do believe the identification of the MET gene is a very important one, and further research should be conducted in order to mitigate the development of autism, I believe that there are other causal factors that should be analyzed before investigating the effects of air pollution on the MET gene. The fact that air pollution is detrimental to the human body is a statement that cannot be disputed. It causes a plethora of cancers as well as respiratory, cardiovascular, and nervous conditions that hinder the day-to-day life of individuals. I would argue that air pollution can is the cause for genetic mishaps that ultimately lead to hundreds of diseases, malformations, and conditions. The fact that it affects the MET gene does not surprise me in slightest. Like Felisha said, looking for a time period in which the MET gene is most susceptible to air pollution would be a more effective study in preventing the development of Autism. Moreover, identifying the specific chemicals in the air and thei chemical interactions with the MET gene would enable scientists to further develop preventative means for pollution exposure.

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  38. GWEI studies definitely prove to be useful in determining environmental factors that can exacerbate or increase the risk of disease. I've always known that autism has an environmental and genetic link, but I never would have guessed that the quality of air can lead to an increased risk of autism.
    I think it's always been known that poor air quality is often associated with poor health, but I think GWEI will be able to further the understanding between the quality of environment we live in and the diseases we may be at a higher risk for.
    GWEI will obviously be limited by confounding variables, since only one environmental factor seems to be studied. This study itself is vague in saying air pollution, so further studies may need to be done to see what part of air pollution specifically is increasing the risk--is it pesticides, burning fossil fuels, or some combination of many air pollutants.
    I think GWEI may be useful in discovering potential links between cancers and the environment, and what exposures cause disease. We all know that certain exposures can cause cancers, but I think GWEI may be able to further our understanding of where cancer comes from.

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  39. With the understanding I have gained about external environmental factors affecting genes through epigenetic processes, the inclusion of GWEI studies seems to be appropriate as future research is conducted. I was very surprised, however, to see that something like air pollution could be linked to Autism in children. As we learned last week with GWAS, genetic associations are becoming more widely discovered; however, I noticed that metabolic diseases are more easily associated with genetic and environmental factors. For a disorder like ASD that is mental more than metabolic, I wonder how such a seemingly obscure factor such as air pollution can be linked to a disease that is still fairly questionable in terms of causation. I look forward to seeing future research regarding GWEI and how it will help change the way clinicians approach disease treatment.

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  40. This week in class I learned about Geographic Information Systems (GIS). I knew there was some form of GIS out there but I did not know that it had a name and that it is widely used in research. I think GIS is good tool because you can learn so much about a population or area by strategically mapping out pertinent information.

    Dr. Fabian brought up the case study about a town in Massachusetts looking for a correlation between cancer and an industrial plant in their town. I found this interesting because through GIS they found out that the increase in breast cancer in the town had nothing to do with their environment. Instead, the cancer rates were due to increase detection because the people in the town were able to afford healthcare and receive routine check-ups. Therefore, breast cancer rates increased because of the ability to afford screenings. It is amazing that this information was learned through GIS. After Dr. Fabian's lecture, I believe that more research should be done using GIS.

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