Saturday, February 27, 2021

Armadillo Quadruplets shed insight on human identical twin DNA expression

 



    The nine banded armadillo is wholly unique when it comes to its offspring. Without fail, a female armadillo will give birth to quadruplets, all genetically identical. This is due to the fertilized egg splitting twice, creating four embryos before they are implanted in the uterine wall. Also that nine banded armadillos can have distinctly differing personalities and behaviors after birth is also intriguing for the scientists, but still have the same genes. There could be also slight physiological differences between offspring. Since armadillos have the 32 pairs of chromosomes to play with , it could lead to greater variety of the genome. Also that early in development, the X chromosome of the embryos will start suppressing parts of the genome at random. Silencing some genes while activating other genes that make slight differences in the offspring's DNA. Also they factor in the environmental changes that could affect behavior, the majority of how the personality is determined is still a black box . What ever genes that affect personality go in, the expressed personality and behaviors come out.

Louisiana research facility studies the nine banded armadillo for Hanson's disease (leprosy) and its transmission to humans, possible inheritance, testing methods to detect leprosy ,sequencing the genome and strains of leprosy and medicines to treat the disease. Scientists could have new model to study gene expression and heritability. 

It could shed insight on how human identical twins could have differing genes from the same sequence and how it affects their health. 


Wednesday, February 24, 2021

Hundreds of new genomes help fill the bird tree of life

 



On this planet, there are more than 10,000 bird species. Recently, scientists have gained a better understanding about these feathered animals and the evolution behind them. This new found knowledge came about when a international team of researchers released the genetic instruction books of 363 species of birds. Within this book was 267 genomes that were assembled for the first time ever. Scientists were then able to use this new data to figure out the varied traits of birds like adaptions for flight, etc. 

Researchers then took the DNA from bird tissue samples from 17 scientific collections that span across the world. This data was around 92 percent of all modern bird families including chickens and even a rare species like the Henderson crake. Ornithologist Michael Braun of the Smithsonian National Museum of Natural History stated Braun says that the "data can be used better understand everything from the parallel evolution of flightlessness in ratites like emus and kiwis to the evolution of vision and song learning in birds overall". Researchers have already found peculiarities in some of the genomes and don't plan to stop assembling and releasing genomes until ever species is included.

I think this is a great advancement dealing with the evolutionary history of birds. I hope that more genomes are discovered so that we can have a better understanding of the bird tree of life and all the different traits they have. I also would like to learn more about birds in general and all the different types there are.

Links: 

https://www.sciencenews.org/article/birds-species-genomes-tree-of-life

https://www.nature.com/news/tree-of-life-constructed-for-all-living-bird-species-1.11712


Monday, February 22, 2021

How malaria parasites hide from the human immune system

 Erin Garcia de Jesus outlines malaria parasites in the human immune system in this article. Malaria parasites hide out in the human body by keeping the cells they infect from clinging  to blood vessels. They do this during Africa's dry season since mosquitos are scarce so the parasites have a hard time spreading. Silvia Portugal her colleagues did experiments on dry season and wet season parasites and they found that blood cells infected with malaria use certain proteins to adhere to blood vessels. There is a loss of stickiness  and this  could be because of two things: Either because the parasite makes fewer of these proteins or because the  proteins are different in some way.  Parasitologist Abdirahman Abdi says  that to narrow down which genes may be affecting stickiness researchers might need to compare genetic activity in parasites at the same stage. It's crazy to think that malaria can actually hide itself in the human body, undetected. Scientists findings help researchers better understand how these parasites turn on and off their genes during the wet and dry seasons so more tests can be conducted. 


This gives extensive information about malaria, it's diagnosis, treatment, etc.

Genetic risk factors for Alzheimer's also raise the risk of getting COVID-19

 In this article written by Tina Hesman Saey, it is explained how a genetic variant that raises a person's risk of developing Alzheimer's may also aid in being more susceptible to COVID-19. People with two copies of the APOE4 version of the APOE gene are 14 times more likely to develop Alzheimer's than people with two copies of APOE3 version. They are also more than twice as likely to test positive for coronavirus. Researchers calculated that 410 out of every 100,000 people with two copies of the APOE4 version of the gene would test positive for coronavirus. This is compared with 179 out of every 100,000 people with two copies of the APOE3 version testing positive. Researchers finding this connection between the variation of the gene and COVID-19 could help people know if they are at a higher risk for testing positive if they have two  copies of the APOE4 variant. 


This provides more information outlining the APOE gene as a whole and its relationship to Alzheimer's and other health conditions. 

Saturday, February 20, 2021

Penicillin allergies may be linked to one immune system gene

  

    

     Jeanne Erdmann writes in her article that people who have reported getting an allergic reaction to the drug Penicillin may have a vulnerability on the HLA-B gene. Penicillin is a antibiotic that is used against many different bacterial infections but 10 percent of people have reported to be allergic to it. Penicillin is not the only drug that makes the HLA-B gene to produce a bad reaction in the bodies of humans. Studies have shown an HLA-B variant to have adverse reactions to an HIV/AIDS medication called abacavir. 

    600,000 electronic health records from people who reported allergic reactions were used in the penicillin study. Researchers need this information so they could go through the DNA in search of genetic variations that cause the bad reactions. Fortunately they found it on chromosome 6 on a variant called HLA-B*55:01. Then they used a genetic-testing company called 23anMe to go through 1.12 million people who had a European ancestry in order to see if they could find the same link/variant which they did. They also did this with East Asian, Middle Eastern, and African ancestries and found nothing. Of course this is very new study and its seems to be a few holes that researchers need to fix. Nonetheless I think this is a very important because we can maybe find a way to make penicillin work for people who have minor allergies to the drug. Some alternatives don't work as well as Penicillin making it harder for the patient so if they could alter the drug so the patient won't have a reaction would have an impact on the healthcare world.     

    The image used was from this link.        

Dire Wolves are Distantly Related Dire Canines ?

 


    Most people know of the dire wolf, the megafauna canine that hunted bison, competed against saber tooth cats for resources and eventually dying out at the end of the last ice age. Others might know dire wolves as the symbol of the Stark Family from A Song of Ice and Fire or Game of Thrones. Hulking massive wolves that could be warged to see from their eyes or attack others. Those interpretations of dire wolves are overhyping the dire wolf when in reality, it could have been a coyote on steroids. 

In a Science Magazine article, dire wolves are only now recently given their own genetic line in the canid family. Far away from the other branches such as foxes, jackals, wolves and coyotes. In fact the La Brea Tar Pits, the resting places of hundreds of dire wolves, mitochondrial DNA was taken and compared to several living canid species in the United States. The results were striking, as the grey wolf diverges from the dire wolf very early on in genetics.There was also no hybridization between grey wolves and dire wolves, meaning that their DNA was incompatible .Coyotes and grey wolves regularly hybridize, only adding to the suspicion that the dire wolf was another beast entirely, genetically speaking. However, the dire wolf DNA genome is incomplete, thus leaving room for genes that do tied them to the grey wolf. 

Since dire wolves were specialized in hunting megafauna, it is a widely believed theory that they died out when their prey also died out due to climate change and human competition.Their phenotype was also  .Unable to adapt, dire wolves became another extinct species, while smaller canids such as coyotes and grey wolves flourished.

If that genome of the dire wolf is ever completed, It would change how the canines in the United States came to be. Also their recreation of their looks would also drastically change. 




Wednesday, February 17, 2021

New Mutations being created due to Coronavirus Variants

In an article from the New York Times, scientists writing a study have discovered that there are possibly new variants that are creating mutations that could possibly affect people more effectively and easily than the virus gene. The protein spikes latch onto human cells vigorously then moves on releasing their genes into the human body affecting close cells. The scientists involved in the research gathered positive coronavirus test results to try and factor out how the mutations are being created due to the variants. They also stated that the 677 mutations have altered the spike protein that is close to the spot where our proteins will nick the virus. 


Dr. Soumya Swaminathan, who is a chief scientist at World Health Organization (WHO), recently talked about the new variant that is N501Y mutation. This mutation has the same effects as the coronavirus, in terms of how it is transferred from one person to the next. The N501Y mutation was found in the UK and South Africa, and researchers have found that it spreads more quickly and is more infectious.

From reading both articles and gaining a better understanding of the coronavirus and the new variants being created and causing these mutations, I think the same way it is recommended to slow the spread of the virus is the same way we should be treating these new mutations. As Dr. Swaminathan said, we have to keep following the same guidelines that have been set out by the Center for Disease Control and Prevention (CDC) to keep these viruses at bay.


Tuesday, February 16, 2021

Some identical twins don’t have identical DNA

 

Identical twins are determined to be genetically the same and often only differ by 5.2 genetic changes. They come from a single fertilized egg and can also be referred to as monozygotic twins. Recently, a new finding suggests that identical twins may not be carbon copies after all. 

In Iceland, researchers conducted a study looking at the complete genetic makeup of 381 pairs of identical twins. Only 38 of those pairs were duplicates of each other and had the exact same genetic makeup. Most of the DNA pairs consisted of a couple differences that the researchers suspected arose either before one embryo split or very early in development. Shockingly of the 381 pairs, 39 of them had more then 100 changes between the twins. Ones theory that resulted from the study was that more uneven splits of the embryo can lead to a greater number of differences.

I was shocked to find out that identical twins may not be exact duplicates of each other. I was always taught that identical twins didn't have any differences when they are born. I hope more research is done regarding identical twins because I would love to learn more.

Links:

https://www.sciencenews.org/article/some-identical-twins-dont-have-identical-dna-genetics

https://www.the-scientist.com/news-opinion/identical-twins-accumulate-genetic-differences-in-the-womb-68324

Saturday, February 13, 2021

When Evolution hands you Citrus

 


    No other fruits other than the apple has pervaded our taste buds so distinctly than citrus. Whether lemon, lime, grapefruit, mandarin, orange or many others, the tart yet sweet flavor has no comparison to any other food. In a 2018 BBC article, the origins of citrus have been traced back parts of Southeastern Asia. The specific regions named in a Nature Article correlate to modern day Yunan province of China, Assam province in India, in the shadow of the Himalayas and Myanmar. Then from there it had spread to the Australian continent, probably by oceanic currents. Some species of citrus drifted over to other islands, becoming genetically isolated from mainland citrus and growing into new species.

    From that point on crossbreeding or interbreeding, whether by accident or intentionally by humans, diversified the citrus profile. Adding flavors, new tolerances for differing climates, or even mixing up for a change. Citrus has com a long way for the monsoon sodden Southeast Asia to becoming a fixture in supermarkets and breakfasts. 


This would be intriging to see what the future for citrus would turn out. Would they remove that orange residual on fingers when peeling them. How about a sourer flavor that would rival artificial candies? The qualities goes on and on that could be changed for citrus. 




Friday, February 12, 2021

Lizard-like tuatara carry two distinct mitochondrial genomes

    

    

In this Science News article it states that researchers have discovered two distinct mitochondrial genomes in the Tuatara, these extra set of genes may be the reason why the Tuatara are tolerant to the cold which is very unique for a reptile. In Tuatara scientist discovered evidence of two distinct copies of genetic instruction manual for making mitochondria in a vertebrate. Mitochondria is important for building the structures and to keep them going. Finding this discovery could not only help other reptiles but humans as well when deal with different kinds of diseases. In 2012 the Tuatara Genome Project was created to decode the Tuatara's genetic makeup which was led by Neil Gemmell. The team was provided a sample of the reptiles blood and what they found was that the Tuatara's genome is 50 percent larger than the human genome.

    Further investigation of decipher the DNA which they compared by chopping it into small pieces with the overall structure they found differences in the mitochondrial DNA which appeared to have striking differences in their gene sequences. This created many of the people working on the project to be stunned because usually mitochondrial DNA is inherited by the mother's egg resulting in a single copy of mitochondrial genome not two copies. They conclude that the genomes were different by 10.4 percent so when comparing it to humans and chimpanzee mitochondrial genomes differ 8.9 percent. 

    I think this discover is very important because if we could find the genetic basis of what causes them to have two distinct mitochondrial genomes we can help find treatments for human metabolic diseases. The picture use above is from Neil Gemmell own experiment article where you can also find a little bit more about the Tuatara. 

People With Dementia are likely to get Coronavirus


This article from New York Times explains the recent study that has shown that people with dementia are more prone to get infected with COVID-19 because of their old age, living in nursing homes, and people with conditions such as asthma, diabetes, cardiovascular disease, etc; which are all known risk factors pertaining to COVID-19. As the study suggested, people who are around the elderly need to be more aware of their surroundings and be responsible to make certain that they are wearing masks and keeping a safe distance. 

The data collected for the study was based hospital records was based on 61.9 million electronic health records from demographics of 18 and older within the United States. According to Deccan Herald, the researchers who obtained these medical records had to adjust their data to count for the risk factors being old age, living in the nursing home, obesity, etc before they were able to determine that Americans with dementia were more likely to contract the virus than people without. When the study was concluded, it showed that Black people with dementia had a higher risk of getting COVID-19 than White people. The vulnerability that is causing this might include physiological and cognitive factors. 

I think that it is even more critical now to follow all the guidelines that have been recommended by the Center for Disease Control and Prevention (CDC) in order to maintain and reduce the widespread of COVID-19 because it is affecting the elderly.  

Thursday, February 11, 2021

New Genetic Blueprint Found in Parasitic Plants


Newfound research on the genetic instruction book of the Sapria genus reveals the lengths to which it has gone to become a specialized parasite. The new discovery illustrates the level of commitment S. Himalayana and its relatives have given to evolving a parasitic lifestyle and provides a comparison to other extreme plant parasites. 

Based on the findings published by Current Biology, most of the Sapria genus have lost half more than half of their genetic material. Not only that but plants like the Sapria Himalayana and their genomes were used for research. Findings showed they had completely removed the need for stems, roots, and even any photosynthetic tissue—and based on further research, even chloroplast genome have vanished

Charles Davis, an evolutionary biologist at Harvard University states that these genetic variations from such parasitic plants have left biologists confused by the sudden change. Such obvious plants recognize by their “rotting flesh” smell, are no longer producing flowers. He notes, “these plants have lost half of their genes, yet they still survive.” 

However, further investigation into this interesting genetic modification will allow researchers to determine some of biology’s limits, which I think will benefit us greatly. 

Links:



The Unethicality of Human Cloning




    A multitude of possible technological and biological advancements arise from human cloning: ridding infertility, understanding and combatting disease, eliminating liver and kidney failure, reversing the aging process, saving endangered/extinct species, etc. The reproductive cloning of humans will grant researchers a better understanding of the human genome, therefore allowing them to successfully pursue the aforementioned possibilities. Even with the numerous beneficial aspects, human cloning (on an individual scale, not with tissues) has been called for a United Nations ban by more than 60 of the world's leading science academies. Why would these science academies push for the ban of human cloning knowing the endless opportunities it may provide?

    Psychological, social, and physiological risks associated with the reproductive cloning of humans are condemned universally. These risks introduce an increased likelihood of the the loss of life. The cloned embryo requires thorough investigation to prove its fitness and viability; even after implanting the successful cloned embryo into the womb, the pregnancy itself may fail. The loss of one life is constitutes as too much. In 2007, an experiment suffered through 100 failed attempts before successfully cloning a macaque.

    Additionally, human reproductive cloning endangers individuality. Human identity would be compromised and diversification would decrease. Monozygotic twins, colloquially known as identical twins or natural clones, often report lacking a sense of individuality. The birth rate of identical twins is 0.4% (1 in 250, or 4 in 1000). Logically, the increase in "clones" ensues an increase in those reports.




https://science.sciencemag.org/content/277/5323/195.full

https://www.britannica.com/science/cloning/Ethical-controversy





Tuesday, February 9, 2021

Climate Change Drove Woolly Rhinoceros to Extinction: DNA Study

 

Researchers have analyzed a complete nuclear genome and mitochondrial genomes from Coelodonta antiquitatis otherwise known as the extinct woolly rhinoceros. Their findings concluded that the population of the woolly rhinoceros remained stable until temperatures began to rise too high for the cold adapted species. This species first appeared 350,000 years ago and became extinct 14,000 years ago. Initially it was thought that humans were the cause of the woolly rhinoceros disappearance because data showed that humans first appeared in Siberia right around the time the population went extinct. Recently several discoveries showed much older human occupation sites. So the decline of woolly rhinoceros doesn't coincide with humans appearance. Professor Dalen and his colleagues wanted to investigate the woolly rhinoceros demographic history so they studied DNA from 14 individuals. 

By looking at the genetic diversity of the genomes, they were able to estimate the woolly rhino populations before their extinction. The population began to increase at the start of a cold period 29,000 years ago and remained constant. The population remained constant long after humans began living in Siberia and didn't start to decline until 4,500 years before their extinction. Researchers also found a genetic mutation in the DNA that helped the animals adapt to the cold weather. They believe the adaption may have declined due to a brief warming period known as the Bolling- Allerod which happened during their extinction. I do believe that climate change and global warming may have had a hand in the extinction of the woolly rhinoceros and that humans may not 100% at fault. I hope that more research is done on this subject.

Links:

http://www.sci-news.com/paleontology/climate-change-woolly-rhinoceros-extinction-08745.html

https://dnascience.plos.org/2020/09/03/extinction-of-the-woolly-rhino-ancient-genomes-point-to-climate-change-not-overhunting/

Friday, February 5, 2021

When will "Designer Babies" be ready?


 

CRISPR technology has been the newest technology in the science world that will continue to move forward. But it is still not ready to create “designer babies” yet. Although it was recently used to create the COVID vaccine, CRISPR-Cas9 more specifically is reportedly still not ready for use, also from an ethical standpoint as well. One reason is still due to the unknown long-term effects it can have. Studies have shown that there have been still some unwanted changes occurring, even with how accurate the technology is. 

Still remembering back to the illegal experiments performed by Chinese biophysicist in 2018, He Jiankui, carried out when editing and allowing the birth of twin girls for resistance to HIV infection. HIV would enter through a protein, and Jiankui disabled this protein by editing & disabling CCR5. Many scientists disagreed with this approach and one main reason is due to the fact that is not the only way HIV can enter a cell. CRISPR-Cas9 still has a lot to prove in terms of precisely editing without causing other adverse effects as well as ethically being allowed by nations. But I also believe it will be the future of technology and hopefully help eradicate the genetic variations & diseases that cause distress to so many families. 



https://www.nature.com/articles/d41586-020-02538-4

https://www.nature.com/articles/d41586-018-07545-0

Thursday, February 4, 2021

Tracing the Evolution of Penguins


    The genealogy of penguins originates near the Australian coast during the Miocene epoch, roughly 22 million years ago. Not at Antarctica as was theorized before. Then the ancestors for the two largest penguins, the emperor and king penguins separated from the Australian proto penguins to colonize Antarctica. Then about 10 million years later, other penguin families began to move away from Australia and left for other places such as Southern Africa, South America and even up north as the Galapagos Islands.While other penguin families remained on Australia, the new penguins found unexploited niches that  .From there on, new adaptations such as heat tolerance, more efficient oxygen use, and maintaining osmosis due to higher salinity in seawater.

    The penguin population really started to expanded only about 70,000 to 40,000 years ago, just after the end of major glaciation. Penguins do favor the colder temperatures and sea ice cover for breeding opportunites. Worringly, with the continuing threat of climate change, several penguin species such as Galapagos and the Gentoo are currently experiencing population decline. It took millions of years for them to adapt to the cold, now they are barely catching up with gradual warming of the oceans. 






Links: 

https://www.pnas.org/content/117/36/2230
3

 http://www.sci-news.com/biology/evolutionary-history-penguins-08755.html