Genetics of child aggression, a systematic review

This article covers how genetics relates to childhood aggression. This article discusses 87 different studies that all analyze the factors that play into aggressive behaviors in children. It was found that genes do play a large role in the risk of aggression in children. Many genes and pathways play into this including dopaminergic, serotonergic, vasopressin, and oxytocin systems. 

The article mentions that while extensive research has been done, further research is needed in order to fully comprehend the linkage between childhood aggression and genetics. This research is important because understanding the relationship will allow specialists to identify childhood aggression early and be able to come up with strategies for prevention and intervention. 

Links:

https://www.nature.com/articles/s41398-024-02870-7

https://www.chop.edu/conditions-diseases/disruptive-behavior-disorders-children

" Scientists Spot Gene That Could Help Cause Miscarriages"

      A recent study from Rutgers University has identified a genetic variant in the gene KIF18A that accelerated reproductive aging, increasing the risk of miscarriage in younger women. The research shows that this mutation causes the production of eggs with an abnormal number of chromosomes, which causes miscarriages. Using Data from an in vitro fertilization clinic and experiments with lab mice, scientists found a link between this variant and bad egg quality. 

This discovery is big because it provides a better understanding of the genetic factors of infertility and miscarriage. According to the researchers, these findings could lead to targeted genetic testing, allowing women to better plan their reproductive health. Women with high genetic risk may choose to freeze their eggs at a younger age or start trying for children earlier. This could help many women and families better plan for their futures. 

Personal opinion: 

This research is big for fertility science. Identifying a gene directly tied to miscarriage provides clarity for many women who have faced unexplained fertility struggles. It's crazy to think that in the future, genetic testing could help individuals make informed decisions about their reproductive health. Some questions come with this kind of research for women and families, like how affordable it would be to see if you have these genes. I think this research and discoveries with fertilization are very important and could change many people's lives. I feel like it could protect people from constantly feeling the loss of miscarriage, which is heartbreaking for many families. 

      

Links: 

https://www.usnews.com/news/health-news/articles/2024-11-26/scientists-spot-gene-that-could-help-cause-miscarriages 

https://ritms.rutgers.edu/news/researchers-zero-in-on-genetic-variant-tied-to-miscarriages/

Tags: #Genetics, #Fertility, #Miscarriage, #reproductive, #Research, #Health, #Eggs, #Sperm, #FamilyPlanning, #Pregnancy, #Gene 

Gene Behind orange fur in cats found at last

 Scientists have spend more than 60 years unsuccessfully trying to find the gene that causes orange fur and the patchwork of colors in calicos and tortoiseshells. Two different studies found finally the mutation and discovered the protein that influence this mutation. Tortoiseshell and calico cats are the offspring of a black cat and an orange cat. The multicolored cats are mostly female suggesting that chromosomes X is the responsible. Female cats inherit a X chromosome from each parents but during embryonic formation cells would need only an X chromosome and will choose randomly which one to express. The other X chromosome will inactivate. So tortoiseshell fur depends on which chromosome was inactivated in difference part of the skin. Calico adds to this already particular situation the withe fur which through another genetic mechanism shut down pigment production. 

In most mammals red hair is cause by a mutation of the surface protein Mc1r that determines if melanocytes needs to produce a dark pigment or the lighter red-yellow pigment for skin and/or hair. If the protein Mc1r is less active the red or blonde hair will occur. Unfortunately this mutation didn’t seem to explain why cats had orange fur since the protein and the mutation are not located on the X chromosome. A team led from Greg Barsh, collected samples of red fur from cats fetuses and measured how the skin cells express the gene and the color by measuring the amount of RNA that each melanocyte produced. Turned out that the melanocytes from the orange cats produced 13 times more RNA from a gene called Arhgap36. The gene is located on the X chromosome which led to think that this was the responsible. The DNA sequence of the Arhgap36 protein shown not a mutation on the gene but a deletion of part of DNA that doesn’t affect directly the protein but that is involved in regulating how much it produced. Searches on genetic databases have shown that every single orange, calico and tortoiseshell cat have this particular mutation. The discovery was preprint on the server bioRxiv.

 A separate study from Japan confirmed this theory. 24 feral japan cats and 258 cat genome around the world revealed the same genetic deletion. Moreover, researchers also found that calico cats have more Arhgap36 in the orange regions compared to the black and brown ones. It has also discovered that the gene is subject to X inactivation since it silences one of the two X chromosome in females. The two team respectively found out that the increase level of Arhgap36 in melanocytes activate another way for  the cell  to produce the red pigment regardless if the MC1r is active or not. This discovery is very interesting because it is  unusual that a deletion instead of a mutation makes a gene more active rather than less. Moreover, the discovery of a new molecular pathways for hair color it was unheard and unexpected but shine a light on how complex is gene expression. This discovery also prove once again how RNA have a crucial role in controlling gene regulation and expression of different phenotypes.  

Preserving DNA with Amber-like Precision: MIT’s Revolutionary T-REX Method

 DNA is the blueprint of life but it is also used for storing data. Preserving DNA for long periods requires careful environment control. MIT scientists have introduced a new approach to DNA preservation using a method inspired by amber. Amber is the natural material known for encapsulating ancient life forms.

This innovation is called Thermal-Reactive Embedding of Biomolecules by X-linking (T-REX). It embeds DNA into a durable polymer matrix, shielding it from heat, moisture, and environmental degradation. It allows DNA to stay stable at room temperature without having to keep it refrigerated. The DNA can later be retrieved intact using a special chemical process. This makes the storage both secure and reversible.

My Thoughts:

The idea of safeguarding DNA at room temperature with an amber-like polymer feels like a bridge between science fiction and reality. It is incredible to think about how this innovation could reshape both digital storage and personalized medicine. This step symbolizes sustainability by offering an eco-friendly alternative to energy intensive storage methods  

https://news.mit.edu/2024/scientists-preserve-dna-amber-polymer-0613 

https://www.isaaa.org/kc/cropbiotechupdate/article/default.asp?ID=20864#:~:text=To%20address%20the%20DNA%20storage,from%20heat%20and%20water%20damage

Crops Designed to Survive in a Warming World

 As climate change makes farming more difficult, genetically engineered crops are becoming an important solution to help ensure we have enough food. Scientists are developing crops that can handle tough conditions, like drought, heat, and pests. For example, drought-resistant corn and soybeans are being created to conserve water in dry areas. Other crops, like insect-resistant cotton and corn, produce their own natural pesticides, which reduces the need for harmful chemicals. This makes farming more sustainable and helps farmers deal with the unpredictable effects of climate change.
These crops have the potential to make farming more efficient, allowing farmers to grow more food using fewer resources. They can also reduce the environmental harm caused by farming, such as overuse of water and pesticides. This is especially important as the world’s population continues to grow and climate change makes farming harder.

However, there are some concerns about these crops. People worry that genetically modified (GM) plants could crossbreed with wild plants, creating new problems like resistant weeds or pests. While studies show that GM foods are safe to eat, there are still debates about the long-term effects on health. There’s also the issue of big companies controlling the technology behind GM crops, which could make them too expensive for small farmers, especially in poorer countries.

Surprise RNAs solve mystery of how butterfly wings get their colorful patterns

Naturalist figured out how butterfly wings acquire their complicated pattern and varieties of colors such as red yellow white and black striping. In 2016 geneticists thought that most of the wing-pattern variations are encoded from protein producing gene called cortex. Three team have now instead proved that a different gene that was missed in previous researches is the key. The final product of the newly discovered gene is not a protein but RNA (lncRNA for long noncoding RNA), which function is to regulate and turn on and off genes that are responsible for the pigmentation of black and pattern on the wing. 

The discovery was possible through a mutant butterfly that was put on sale on Ebay and bought from biologist Luca Livraghi of George Washington University after being flagged from a colleague. The butterfly in case was a completely white butterfly of the genus Heliconius. The team sequenced a dozen of those mutant ivory butterfly and realized that there was a deletion in the region of the cortex gene. The researchers then realized that the deletion of DNA included a sequence that encode the lncRNA that no one had examined before. The team then decided to expand the research to other species of butterflies. Using  the gene editor CRISPR the team disabled the lncRNA gene in painted lady butterflies (Vanessa cardui) which are easy to breed in lab and had colorful wings. The CRISPR edit produced white-winged painted lady butterflies just like the Heliconius. Moreover the team tried to disable the cortex gene and realized that it doesn’t affect the color of the wings. 

The results of this study were also proofed to be right and can be extended to other butterfly species that are distantly related to it. A Cornell evolutionary biologist (Robert Reed), joined effort with Livraghi and used the same CRISPR techniques on buckeye butterfly. By cutting different parts of the lncRNA,  Reed was able to produce butterfly with little or no color. Moreover, Antonia Monterey and Shen Tian from National University of Singapore, while focusing on microRNA found that one of those short RNA sequence was active on bush brown butterfly (Bicyclus anynana) just like Livraghi found for his butterfly. The Singapore team disabled in an experiment the DNA that encoded the microRNA, called mir-193 and the bush brown butterfly wings became lighter just as predicted from the other team. The experiment was then repeated by cutting mir-193 on Indian cabbage white( Pieris canidia) and changed the wings from black-patterned to white. This confirmed that the microRNA was a short part of the longer lncRNA. 

It is crazy to think how such a short piece of information can change drastically the phenotype of butterfly  species that are very distantly related. Because the microRNA mir-193 is proven to be conserved in animal kingdom, scientists and researchers think that this small piece of  RNA can be used in other species to regulates genes. Moreover, the focus is always have been on DNA but RNA turned out to be as much as important as DNA not only for transcription and translation but also for gene regulation. 

A gene edit affecting one wing (right) of this Heliconius erato radically changed its normal color pattern

 

"Out of one, many"

     It is a well known fact that an alteration to a gene sequence, whether it be a mutation, deletion, or substitution, can have varying effects on the final product of that sequence. Sometimes it doesn't affect the sequence at all while other times the results are catastrophic. So it may seem mundane when a research team in the University of Pennsylvania observed such adverse effects when they changed a single gene within a sequence. However, it was what they were aiming to achieve that makes this so interesting.

    A led by plant biologist Aman Husbands from the University of Pennsylvania were studying a group of HD-ZIPIII transcription factors, TFs, when they realized that despite using the same materials, these TFs interpreted sequences completely differently. To further study this, they chose two different TFs, CORONA, CNA, and PHABULOSA, PHB. They found that these two TFs would bind to the same region on the DNA but noticed a difference in their START domains, the lipid-binding region of the TFs. Concluding that these START domains dictated how these TFs interpreted the sequence, they decided to switch the START domains of CNA and PHB. By mapping out the results, the researchers found that the START regions regulated what genes the TF could bind to, ultimately changing the final product. Aman Husbands, parodying a Latin phrase, called this "Out of one, many" referring to how a single change in the START domain creates a brand new template for binding sites, one change, many possibilities.

    As with most discoveries, the possible medical use for this is immense. While this type of experimentation is new, the researchers are trying to see what different kinds of changes to the START domain will cause. It would be interesting if this could be used to fix genetic disorders caused by mutations or if it could be used to suppress harmful disorders.

Y Chromosome Analysis of Horses

 

Scientists are attempting to trace the paternal line in horses by using the Y chromosome. The Y chromosome has always been difficult to study since it contains many repeating sections and palindromes. Since computer technology has made it easier to analyze it, a worldwide collection of horse DNA samples were able to be analyzed, and the ancestries of these horses were able to be traced. Horse and human history are closely linked, and humans have used stallion mediated breeding with horses due to the fact that it is easier to trace a stallion’s fertility than a mare’s. Pedigrees are used to trace horse ancestry today, but since they are done manually then only go back a few generations. With the Y chromosome analysis, however, they are able to go back many generations and examine evolutionary lineages within the horse’s paternal ancestry. This will allow horse breeders to better prevent inbreeding and maintain genetic diversity.

In my opinion, this is a very useful and unique effort. Mapping the Y chromosomes of a variety of horses in order to examine their evolutionary development and lineages on their paternal side proved to be extraordinarily beneficial. By gaining the ability to trace the genetics of horses across multiple generations, we can better keep record of particular lineages and ensure that horses with similar lineages do not breed together in order to prevent genetic defects. We can work to better conserve and enhance genetic diversity within horses. We are also able to better analyze breeding influences over time and how they connect with human history as well.