Friday, February 23, 2024

Can I Have Twins Even If They Don't Run in my Family?

  This article discusses the role of genetics in determining the probability of having twins. It explains that the likelihood of conceiving twins is influenced by both genetic and environmental factors. Monozygotic (identical) twins occur when a single fertilized egg splits into two embryos, while dizygotic (fraternal) twins occur when two separate eggs are fertilized by two different sperm cells. While the occurrence of monozygotic twins is generally not strongly linked to genetics, dizygotic twinning is more likely to run in families. Factors such as hyperovulation, maternal age, ethnic background, and assisted reproductive technologies can also influence the chance of having twins. Additionally, the article provides references to scientific journal articles for further reading on the topic. I found this article very interesting because I always thought that fraternal and identical twins were essentially the same thing, both running in families. I think lots of people believe this too, because I have heard people saying identical twins run in their family. This article disproves this though, basically saying that while fraternal wins usually can be traced back a few generations, identical twins are just a really cool magic trick that occurs during pregnancy and can really happen to anyone regardless of their family line!


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Is intelligence Hereditary?

 The article " Is Intelligence Hereditary" talks about how intelligence is influenced by both environmental and hereditary factors. Although genetics explains half of the variation in IQ across people, environmental influences also have a big impact. This understanding has been helped by research on twins, adoption, and DNA analysis. For example, children who are adopted at birth typically have IQs that are comparable to those of their biological parents.

Many genes contribute to intelligence, according to recent research efforts working at identifying the genes linked to intelligence. But the current research explains only approximately 5% of the individual variation in intellect. It's interesting to point out that from 20% in infancy to 60% in adulthood, there appears to be a growing hereditary influence on intelligence. 

This article, in my opinion, highlights the complex relationships between heredity and environment and intelligence. Without a doubt, genetics is very significant, but environmental variables also matter. The complexity of the human mind is shown by ongoing studies into the genetic basis of intelligence, which also provides hopeful insights. Advances in treating cognitive problems and encouraging individual development may result from a better understanding of the interaction between genes and environment.


Down Syndrome in Ancient Bones

Down syndrome which is also known as trisomy 21 is a condition in which there is an extra copy of chromosome 21. The effects of the extra chromosome 21 are possible heart defects and learning disabilities. A recent study was published in the journal Nature Communications that shows a new method for diagnosing Down syndrome in ancient bones. This new method was able to analyze the genetic makeup of infant skeletons that were dated as far as 5,500 years ago. The method is to sort the fragments of the DNA by chromosome. Then the program compared the DNA from each bone to the entire set in order to pinpoint an unusual number of sequences from a particular chromosome. Before this new method it was difficult to analyze all of the genetic makeup of bones because they will start fragmenting especially from children's bones since they are more fragile. This is a huge step in analyzing genes because it can potentially help learn about ancient diseases. For example according to Zimmer (2024) people in the culture were normally cremated after death, not buried. 

It is interesting to see that new methods are still being found to help understand the past better. I really thought it was interesting to see that Down syndrome babies were found buried instead of cremated. I think it shows a lot to what people back then were thinking about and how they inferred differences in each other. It makes me want to keep track of if they find any other ancient disease from ancient bones. 

Thursday, February 22, 2024

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.     

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Wednesday, February 21, 2024

Gene-editing for Vector Born Illneses

In recent years due to climate change, there has been a distinct rise in vector born illnesses, more specifically mosquito-borne illnesses, such as malaria. Attempts to combat this issue mostly rely on the use of pesticides as a form of mosquito control. Luckily, a company named Oxitec have been developing gene-editing technology as a form of pest control. 

Aedes Aegypti has been the most significant mosquito when it comes to carrying diseases. This species of mosquito was chosen to be tested on in order to prevent the spread of disease. This is done by using gene-editing to produce male offspring that produce female progeny that do not survive to adulthood. This technology was used in Brazil and resulted in a 90% decrease in the Aedes Aegypti population. 

The thought is this, with less population there is a lower possibility of contracting a mosquito-borne disease. This technology could be very useful for the United States, mostly because cases here have also been on the rise. Concerns have been brought to attention about the specific ecological concerns with gene-editing in mosquitoes. Results from trials in the Florida Keys have shown the technology to be environmentally safe and protective. 

In my opinion, this technology could provide the United States with a way to control its population of mosquitoes that carry diseases. I think that gene-editing is a much better form of mosquito control than the use of pesticides. 

Tuesday, February 20, 2024

Does Depression Result From Genetics?

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Have you ever heard the phrase, “depression runs in the family?” The 2021 article posted on FHE Health states that Mental illness is a biopsychosocial disease that has a strong genetic component. Even though the exact set of causes have yet to be determined, if a parent, sibling or grandparent is diagnosed with a mental illness, the likelihood of developing the same or similar kind of mental illness does increase. Genetic disorders appear when abnormalities happen in the person’s genome. These genetic disorders are inherited when a defective gene from both parents is passed to their children and then affect the child’s DNA. 

A study posted in 2018 determined that genetic mental health disorders such as autism, schizophrenia, ADHD, bipolar disorder and depression are traceable to certain inherited gene variations. Functional magnetic resonance imaging scans showed that people with the genetic variation occurring in the serotonin transporter gene demonstrated hyperactivity in a brain area that processes anxiety and fear. This genetic variation is involved in brain cell signaling and communication. However, for depression the association to having this mental illness and its traces of heritability are still unclear. There’s ongoing research which supports the theory that the interaction between genetic and environmental factors increase a person’s chance of developing depression. 

It is very interesting to hear about the science of mental illness and how some mental disorders can be traced back to the individual's inherited genes. I am wondering what further research can be done to further understand the correlation between genetics and mental health. 

Sunday, February 18, 2024

Bipolar Disorder Linked to Genetics?

    In the article written by the National Institute of Mental Health, researchers have identified genetic locations related to bipolar disorder and tell us the possible biological cause for the disorder. The study also compared the overlap between bipolar I disorder (manic and sometimes depressive episodes) and bipolar II disorder (depressive and hypomanic episodes). Bipolar I disorder shows a stronger genetic correlation with schizophrenia, while bipolar II disorder correlates with major depression. Now it is also noted that traits such as excessive alcohol consumption, smoking, and sleeping issues can also affect bipolar disorder. To test the genome and understand differences researchers sampled 57 groups across Europe, North America, and Australia. This includes about 41K people with bipolar disorder, and 371K without. 64 genomic locations were noted as risk loci pertaining to this issue, which means this study identified 33 more than previously identified in previous studies. Those 64 genomes include 161 individual genes where some involve how brain neurons signal each other. This allows targets for biological treatments with specific medication to help treat bipolar disorder.

    Bipolar disorder is a mental illness known for its highs and lows. I truly believe that more research into not just environmental causes but also genetic risks could make someone more susceptible to exhibiting symptoms of this illness. It is interesting to see how they can identify differences in loci that can cause the neurons to not signal properly, but also affect how the medication given to treat it affects our brain. If research can understand biologically how bipolar disorder affects people's brains, we can create more personalized treatments for those who have this disorder.


Genomic Data From More Than 41,000 People Shed New Light on Bipolar Disorder. 2021 Sep 29. National Institute of Mental Health (NIMH).

Bipolar disorder - Symptoms and causes - Mayo Clinic. 2022 Dec 13. Mayo Clinic.

Saturday, February 17, 2024

Smoking Undermines Human DNA That Would Normally Prevent Cancer

Ernie Mundell reported the new research that was found from the Ontario Institute for Cancer Research that emphasized that smoking undermines human DNA that would normally prevent cancer. The research elaborated on how smoking prevents the formation of proteins that control cell development and leads to "stop-gain" mutations in cellular DNA, which prevent the body from producing protective proteins. The article also mentioned that tobacco does a lot of damage to our DNA and has a major impact on the function of our cells. When tobacco smoke enters the lungs, it triggers a dramatic influx of macrophages and neutrophils in the bronchi and pulmonary epithelia, and it triggers tumor development. The products in tobacco can alter the genome of immune cells, whether by implanting chemical adducts in the cellular DNA or by inducing irreversible genetic damage. 

I thought the article was insightful, especially when the reporter explained the reason why more stop-gain mutations can be found in tumors when a person smokes intensely and for a long period of time. I agree with the statement in the article that said, "Everyone knows smoking to be a major cause of cancer." However, I believe that not everyone knows how smoking can damage our DNA and mutations and how it can be prevented.