aminokassid – BioQuakes

Author: aminokassid

Hope for Duchenne Patients?

On March 1, 2019

Duchenne muscular dystrophy is a genetic disorder currently without a cure. It causes progressive muscle degeneration and weakness. Duchenne Muscular Dystrophy, or DMD, is characterized by an absence of dystrophin. Dystrophin is a protein that keeps muscles intact, which when absent lead to a loss of muscle function and strength. This lack of dystrophin begins in early childhood between ages three and five mostly in males with 1 in 5,000 males inflicted and a rare

Dystrophin Protein

occurrence in females. By later ages, individuals are forced into wheelchairs and put on respirators as their diaphragms weaken until an early death usually in their 20’s or early 30’s due to heart failure or an inability to breath.

Despite not having a cure for Duchenne Muscular Dystrophy, scientists are performing the first trials in large mammals, dogs. Many dog breeds can also be inflicted by the lack of dystrophin and thus have Duchenne Muscular Dystrophy. Four of these inflicted dogs have been chosen at only one-month-old to be treated using a harmless virus called adeno-associated virus or AAV. This harmless virus is delivering the CRISPR Cas9 protein gene-editing components to make a single strategic cut in faulty DNA to “exon 51, one of the 79 exons that comprise the dystrophin gene.”

Right Affected Individual Left Unaffected Individual

These dogs were tracked and within several weeks of the CRISPR editing the missing protein was reported in muscle tissue throughout the body with as much as 92% correction in the heart and 58% correction within the diaphragm, which is the main muscle needed for breathing. While there is a clear success in the current trials with improvements greater than 15%, they are still far from human clinical trials as the question still remains if the stable levels of dystrophin do not have adverse side effects. The corrections made using CRISPR was previously noted in having successfully corrected mice and human cells only increasing the hope provided by these trials. The trial is already being called “promising” and might one day be considered “groundbreaking.”

Not only providing hope for those with DMD, but these trials also provide a significant step towards single gene editing to treat an incurable disease. While larger studies are still to be conducted, the individuals working on this study at the Royal Veterinary College in London and UT Southwestern Medical Center in the United States are eager for the study to grow. One such leader in this study, Dr.Olson from UT Southwestern has even gone as far as spawning a biotechnological company called Exonics Therapeutics Inc. with the hope of further optimizing this technology for the clinic on top of his role at the University.

AminoKassid

CRISPR Scandal

By aminokassid

On January 14, 2019

In Student Post

Outrage is widespread in the scientific community, as one man’s choices may have ruined genome editing for everyone. With others calling his actions “premature,” “ethically problematic,” and “monstrous” Doctor He Jiankui remains confident in his actions. His action being creating the first genetically modified babies, twin girls born in November. “He had altered a gene in the embryos, before having them implanted in the mother’s womb, with the goal of making the babies resistant to infection with H.I.V..”

The chaos created by Dr. He’s actions are due to the fact that he failed to receive permission from an ethical board. He claims to have gotten the permission of the hospital, Shenzhen Harmonicare, but the hospital denies being involved. The hospital is even going as far as requesting a police investigation into the “fraudulent ethical review materials.” So without ethical approval, Dr. He seriously violated not only the Chinese government’s laws and regulations created by the Chinese Society for Cell Biology but also academic ethics and norms. He has risked opening the door to designer babies editing everything from eye color to I.Q and physical ability, while the CRISPR creators are attempting to limit the editing to cases of desperate unmet need where the cause cannot be prevented in any other way, unlike H.I.V. which is very easily avoidable in infants.

These twins, however, are the only known set of children to be produced from a trial of seven couples with an H.I.V. positive father and negative mother. Dr. He after deactivating the perfectly normal gene CCR₅ with CRISPR-Cas9 implanted the embryos into their mothers. In deactivating the CCR₅, Dr. He made the girl’s resistant to H.I.V., but also made them more susceptible to West Nile virus and Japanese encephalitis. So while the babies were “born normally and healthy” according to Dr. He, Dr.Kiran Musunuru from the University of Pennsylvania said there was evidence of mosaicism in both twins embryos and Lulu’s placenta was also mosaic. Despite the mosaic placenta, both babies appear to be progressing well for now, but what will happen to them in the future is the unknown. While their health is positive for now, the effects will be felt in their progeny for generations to come in unknown ways as cells with CCR₅ and without are mixed.

With the unknown effects on future children, a lack of shared experimental notes/reports and ethical precautions, and a plea via youtube Dr. He only 34 years old is being shunned in the science community just days before his presentation at the Second International Summit on Human Genome Editing in Hong Kong.

AminoKassid

Welcome to America, here is a risk of obesity?

By aminokassid

On November 11, 2018

In Student Post

Each individual has a personalized micro-biome with trillions of bacteria weighing about half a pound. We receive this microbiome at birth as a departing gift from our mothers, but this microbiome does not remain the same through the years. Studies by Dan Knights from the University of Minnesota have shown, however, that geographic location and diet results in shifts in our gut microbiota.

Figure 1

So what does this mean?

The study by Dan Knight shows that immigration is causing dramatic shifts in new arrivals to the country. These new arrivals surveyed through stool samples are from places in Southeast Asia including 500 women of Hmong and Karen descent. These 500 women varied from individuals remaining in Thailand where most Hmong and Karen people live currently, first- and second-generation U.S. immigrants, and even included 19 Karen women followed through their first six to nine months in their new nation. All of these samples were then compared to 36 European Americans born in the United States.

On the microscopic level, the aforementioned immigrants are facing a shift in the gut microbiota from Prevotella bacteria to Bacteroides. “Prevotella bacteria produce enzymes that digest fibrous foods more common in Asia than the United States. In Thailand, the women ate more palm, coconut, a fruit called tamarind and the bulbous part of a plant named konjac.” This shift in bacteria causes a loss of 15% of microbiome diversity and furthermore does not shows signs of compensating for the loss of native microbes.

As the diversity shifts towards that of European American, obesity rates seem to spike among the population. The immigrants’ obesity rates increased by nearly six times, which is a drastic shift for the immigrants who held an originally low risk of metabolic disease. This shift, however, is still a complete mystery. The researchers cannot pinpoint the true cause as diet, location, medicines, water composition, or an unknown but there is a clear correlation between obesity and the lessened diversity in the gut microbiota. This correlation was discovered through an experiment involving mice injected with germs from obese women. These mice subsequently became heavier despite having the same food as their lean equivalents. Knight and his colleges plan to continue their studies in hope to possibly provide a solution to obesity through the injection of Prevotella, as they are driven by the intense sensitivity and stake of their subjects’ health.

Figure 2: Experiment on Obesity with Mice

While immigration to the United States, a place of opportunity, may appear a blessing it does not come without risks. As the leading nation in obesity, it comes as no surprise that something is causing a drastic shifting in newly immigrated individuals’ gut microbiota and larger micro-biomes resulting in a higher risk of obesity. A gift and a curse, however, this phenomena has resulted in research that could possibly grant new insight on how to prevent obesity.

Males to Become Obsolete?

By aminokassid

On October 14, 2018

In Student Post

“No study in the past [has described] a complete elimination of males,” claims Rebeca Rosengaus, an insect sociobiologist and behavioral ecologist at Northeastern University. Professor Rosengaus’ statement relates to the study by postdoctoral researcher Toshihisa Yashiro and Professor Nathan Lo on Japanese

islands of Shikoku and Kyushu, where termites are evolved to reproduce strictly asexual with a population of only females. The primary question facing the researcher team faces is how does this advanced animal population reproduce without the necessity for their male counterparts? The termite subset of the cockroach family is not the first creature to do so as there are species of hymenopteran insects, both ants and bees, that have gone female. Due to the recent discovery of the evolutionary change, researchers can only hypothesis on the breeding techniques of the all-female termite populations based on similar populations of bees and prior termite activity. In the strictly feminine bee colony, the label queen, which normally mates and holds a sperm-hoarding pouch within her body from males, reproduces by laying unfertilized eggs which only receives chromosomes from their mothers and hatch producing females with double copies of their mothers’ chromosomes at a far faster rate. These termites, however, also varied from their typical monogamous relationships and queen and king breeders to a queen driven society before in order to avoid inbreeding between fertile kings and their own offsprings. So while there are many suspicions on the reproduction of these highly evolved termites, the answer to how they evolved to such conditions are left unknown as the normal order of society is to maintain the health of a colony through sexual reproduction to protect against diseases and environmental changes. Such diseases are believed to be rather rare, however, on the islands of Shikoku and Kyushu, yet this concept is under-researched as of now. These females are surviving after this shift in sexual dependence approximately fourteen million years ago as their all-female band of soldiers are structured far more uniformly and have increased defensive efficiency. These females are not suffering by any means without their male counterparts. The Glyptotermes nakajima species are the underrated feminist heroes of our insect world despite being only a few millimeters long with soft, doughy bodies. What do you think will human males someday become obsolete? Is this the way the world is going or just a random phenomenon?

Amino Kassid

Source Article:

https://www.sciencedaily.com/releases/2018/09/180925110051.htm

BioQuakes

AP Biology class blog for discussing current research in Biology

Author: aminokassid

Hope for Duchenne Patients?

CRISPR Scandal

Welcome to America, here is a risk of obesity?

Males to Become Obsolete?

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