Advancements in Prenatal Genetic Testing

    Embarking on the journey of parenthood very exciting and largely transformative experience for most people. Genetic testing provides an opportunity for expectant parents to gain a deeper understanding of their soon to be baby's genetic health. There is a few different genetic testing options available but they only skim the surface of the amount of potential genetic disorders. The testing that was previously available is said to be extremely invasive, inserting a needle into the uterus to retrieve fetal cells for analysis. Recently discovered though is a new and non-invasive technique (non-invasive prenatal testing NIPT) that just requires a small blood sample from the soon to be mother.

    This non-invasive procedure though not as advanced as it counterpart is more safe and a cheaper alternative to see if there may be any potential signs of genetic disorders before taking the next step of an invasive procedure. Especially being that invasive genetic testing has a chance of miscarriage. Though NIPT is still not as advanced as invasive because it can not identify full chromosomes there are new technologies and advancements being made in order to further the use of blood testing so we can fully terminate invasive testing as an option for seeking prenatal health.

    Genetic testing in my opinion is something very important that should be financially and readily available for all expecting mothers. This is because in the world we currently live in most parents are financially independent enough to be able to afford and take on the responsibility of a child with a genetic disorder. Therapies and interventions being so new also comes with a large price tag that parents should be informed and prepared for when planning for a newborn.     

Articles Cited:

1. https://pubmed.ncbi.nlm.nih.gov/38020177/

2. https://www.nichd.nih.gov/newsroom/news/120623-new-method-prenatal-testing

New non-invasive prenatal genetic screening comes out of clinical study

An article at the Baylor College of Medicine discusses the first commercial noninvasive prenatal gene screening that their genetics team developed in 2017, called PreSeek. The data that was collected during the clinical trials where its accuracy was the main focus. The PreSeek is able to detect several monogenic disorders that are not always picked up by standard prenatal screenings, which helps to provide a better, more through, at the genes of the unborn child. The results that were found during the clinical tests are showing that the non-invasive test are able to provide valuable data for a large amount of common dominant monogenic disorders. The team is currently hoping to make the tests more cost effective and to bring more awareness to the valuable role that non-invasive test have with prenatal care.

I think that tests like PreSeek have the potential to be a valuable asset to prenatal care, as they can provide more information on the genetics of the unborn child that could be life altering to both the parents and future child. Knowing what possible risks that the baby might face, or if there are any major genetic abnormalities that they might have is crucial of the doctors and parents. While current prenatal tests do provide a wealth of information about the genetic makeup of the child, tests like PreSeek help to add even more information that could not be discovered with the normal tests.        

The Dutch Hunger Winter: Starvation and its Effect on Genes

In September 1944, allied forces failed and all trains coming into the Netherlands came to holt. The Nazis planned to punish the Dutch people by blocking all food supplies going into the Netherlands thus, plunging much of the country into famine. By the time Holland was liberated in May 1945, more than 20,000 people had died of starvation. Pregnant people who survived the famine were uniquely affected in that their children would be influenced by the famine for the rest of their lives. When these children became adults they were heavier than average and as they became middle-aged they had higher levels of triglycerides and LDL cholesterol. Conditions such as diabetes, schizophrenia, and obesity were common and they as reached old age it was found that their mortality increased by 10% once past the age of 68.

Dr. Heijmans, a geneticist and Dr. Lumey, an epidemiologist published a paper with a possible answer. Their study suggests that the Dutch Hunger Winter silenced certain genes in the unborn children and they've stayed quiet since. Certain genes are active in some cells and some are quiet and this is set since birth unless something acts upon them, for example a virus; the study of this gene control is called epigenetics. Researchers have found that silenced genes have a collection of methyl groups near by. The researcher speculate that these methyl groups are affected by prenatal conditions thus, can affect the activity of genes. As terrible as the Dutch Hunger Winter was there is a silver lining. This silver lining has allowed researchers to study a unique health outcome that may help us better understand gene silencing and how a pregnant person's environment can affect their unborn child.
https://www.nytimes.com/2018/01/31/science/dutch-famine-genes.html
https://www.verzetsmuseum.org/museum/en/tweede-wereldoorlog/kingdomofthenetherlands/thenetherlands/thenetherlands,june_1944_-_may_1945/the_hunger_winter

Autism is not linked to prenatal exposure to antidepressants

The linkage between giving birth to a child with Autism and exposure to antidepressants is not entirely clear, but progress has been made. Researchers have now come to realize that a woman who is pregnant and depressed, might harm the child more if her depression goes untreated. The effects of depression causes serious effects on the child such as how the child grows, feels, and eats. Exposure to the antidepressants has no correlation. A study down in Sweden showed that newborns exposed to antidepressants were just as much at risk to have autism as kids who were not exposed. More research has to be done to know the exact answer however. This blog was very interesting, I like how it is a relevant topic and still needs more research to be done. Most people now have been effected by Autism whether it is a sibling or a family friend. It would be awesome to further the knowledge on this disorder. I think this goes hand in hand with the theory that needles/vaccinations cause Autism. This proves again that we are wrong and this disorder is much more and needs more research to be done.


Article: https://www.sciencenews.org/article/autism-adhd-risk-not-linked-prenatal-exposure-antidepressants
Related article: http://pubmedcentralcanada.ca/pmcc/articles/PMC3832387/

Ageing May Begin in the Womb

A recent study by the British Heart Foundation has discovered that ageing may actually begin in the womb rather than the moment you are born. The scientists involved in the study have also found that the amount of oxygen a baby receives in the womb can have an effect on their genetic age when they are born.

At the ends of each chromosome there are telomeres which become shorter and shorter as an organism ages. Observing the length of these telomeres can be used as a proxy to measure ageing. This is what is meant when referring to “genetic age”.

Location of a telomere on a chromosome

The study involved providing a portion of pregnant rats with antioxidants while the rest were being cared for in a room with 7% less oxygen. When each group of rats had given birth it was found that the offspring of those that were provided antioxidants had longer telomeres in their blood vessels than those cared for in the room with less oxygen. This meant that those with shorter telomeres aged more quickly and were predisposed to developing heart disease earlier in their life.

Mothers who smoke while they are pregnant have lower levels of oxygen in the womb which can affect their unborn baby just as was simulated with the rats. This could mean that mothers who do this not only subject their babies to a list of possible medical issues but also age their baby faster in the womb. When it comes to heart disease, this study is significant because it provides evidence that the environment an organism is exposed to in the womb can be as influential as obesity and smoking outside the womb.

I found the concept of this study to be interesting as it is bizarre to think that we can age before we are even born. While I am aware that the British Heart Foundation conducted this study around the conditions of heart disease it would be interesting to see how this slowed/accelerated aging would affect the likeliness of developing other disease or conditions and what else could affect this process in the womb

Behavior Linked with Smoking?

     We all know cigarettes are bad for you, but the real question is "how bad"? We all know that cigarettes damage our throats, lungs, and other parts of our body, but scientists are beginning to discover a new problem arising out of smoking. A recent study has shown that mother's who smoke cigarettes during their prenatal stage, are putting their children at greater risk for behavioral problems. Of course, this is usually linked with a genetic risk for behavioral problems, but they are now beginning to understand that the smoking of cigarettes increases their risk of the behavioral problem arising. This is very interesting news as it sheds light onto an already tattered reputation, but no one is complaining. In our current society smoking cigarettes is increasing being looked down upon, and more news like this puts cigarettes deeper and deeper into the hole they have dug themselves into. So, we already know the life threatening side-effects of smoking cigarettes presents, but now that more problems arising. So the question then becomes, "Will people continue to smoke cigarettes?" The answer to that question is YES! People are addicted to cigarettes and will continue to be regardless of the negative effects. So, if you see a mother-to-be walking down the street smoking a cigarette, make sure you warn her and tell her to read this article.

Prenatal tests for Down Syndrome

     Breakthroughs in new tests for prenatal screening allow for women to have more options.   New screenings are more accurate and less invasive.  They allow for screenings of any chromosomal abnormalities while avoiding the risks that amniocentesis imposes.  In the past, the decision to undergo an amniocentesis was based on risk due to the woman’s age and genetic history.  Many amnios were performed but not medically necessary, due to the lack of accurate information provided. The new advancements in screenings that are noninvasive and more accurate allow for women to make well-informed treatment decisions.

     

     The new screenings test the fetal DNA that is found in the mother’s blood.  These tests provide results that detect almost all cases of Down syndrome and result in a false positive result of less than 1% of all cases.  Which is significantly less than older tests.  Noninvasive test results that are positive require an amniocentesis to confirm the existence of Down syndrome.  

     This new noninvasive screening test leads to the possibility of treating a fetus with chromosomal abnormalities prior to birth.  Prenatal treatment such as this, would hopefully allow for the minimization of neurological effects caused by the detected disease.  The developments in prenatal testing and treatment are relatively new and still being tested.  Hopefully within the near future, availability for screening such as this will become more affordable.  It is exciting that such a breakthrough could allow for the discovery of treatments for genetic diseases prior to birth.

http://well.blogs.nytimes.com/2013/10/07/breakthroughs-in-prenatal-screening/?_r=0
http://health.nytimes.com/health/guides/test/amniocentesis/overview.html?inline=nyt-classifier