My parents explained to me that all these changes were due to the error of a single letter among the billions of letters in a long DNA sequence. This error prevents the production of the protein responsible for repairing arm and leg muscles.
Today, I am a doctoral research student in molecular medicine. I study the treatment of hereditary diseases in order to be able to help families like my own. In this article, I will demystify hereditary diseases and show what research is being carried out to treat them.
Let’s start by imagining DNA as a recipe book. Each gene represents a different recipe. The page with the chocolate cake recipe has a nice picture, but there is some information missing. The recipe says to preheat the oven and measure the flour, but the rest of the page is torn. So it is impossible to make the cake. We go ahead and serve our meal made from all the other recipes, but there is no chocolate cake even though this is a particularly important part of the meal.
The same is true for hereditary diseases. In this case, the body can make all the proteins it needs except one. In dysferlinopathy, which affects my family, the missing recipe is the protein that repairs the muscles of the arms and legs. Each hereditary disease has its own damaged page in its recipe book.
Effects of a mutation. (Camille Bouchard), Fourni par l'auteur
To be precise, an error in the DNA is called a mutation. There are different types of mutations. Some are caused by adding letters, like adding an ingredient to the recipe. This addition could lead to a delicious chocolate cake with strawberries, or to a cake that is no longer edible because we added motor oil to it.
Other mutations are caused by the removal (or elimination) of one or more letters (or ingredients), or by substitutions that replace one letter with another. All of these modifications can lead to favourable or non-impactful changes, such as the appearance of the first blue eyes in evolution, or the ability to breathe outside of water. But these modifications can also bring about unfavourable results, such as a hereditary disease or cancer.
There are different types of mutations. (Camille Bouchard), Fourni par l'auteur
From a young age, I understood that my mother was sick due to the error of a gene, but that I would not develop the disease because my father did not have the same error. This is called a recessive disease, since there must be an error in the gene of each of the two parents in order for the disease to manifest. Other hereditary diseases are dominant, meaning that a mutation in the DNA passed down from just one parent is enough to impair the production of a protein.
As part of my research, I look at the DNA sequence of each dysferlinopathy patient to see where the error is.
To try to correct it, I use Prime editing, a technique which makes it possible to cut the DNA near the mutation and rewrite the sequence correctly. Prime editing is a version of CRISPR-Cas9, a technique that allows DNA to be cut at a particular location.
Prime editing uses a protein called Cas9, which occurs naturally in bacteria. This protein allows bacteria to destroy the DNA sequences of viruses that could infect them. The mission of the Cas9 protein is to recognize a sequence and cut it.
When we use Cas9 in our human cells, we attach it to another protein, which rewrites the DNA sequence based on a template. In other words, we give the cell an error-free sequence so that it can go ahead and manufacture the protein on its own. It’s a bit like recovering the original page of the recipe book so you can finally serve the chocolate cake.
So why aren’t we hearing about Prime editing, when it could be used to treat a variety of diseases? Because the technology is not yet fully developed. At the moment we are able to repair DNA directly in cells in the laboratory, but we lack the means to deliver the two large proteins (Cas9 and the one that rewrites) to the cells to be treated (for example, to the centre of the affected muscles).
Prime editing is a technique being studied to correct mutations in different genes. (Camille Bouchard), Fourni par l'auteur
In other words, we have found the chocolate cake recipe, but it’s written on a page that is too large to fit in an email or put in an envelope. Many laboratories, including mine, are looking for an efficient and safe vehicle that will be able to deliver these proteins.
Camille Bouchard, Étudiante au doctorat en médecine moléculaire (correction génétique de maladies héréditaires), Université Laval
This article is republished from The Conversation under a Creative Commons license. Read the original article.
Dreams of space travel started small with the launch of Sputnik-1 by the Soviet Union, and escalated with the U.S. Apollo landing on the moon in 1969.
Six decades later, plans are ramping up for space tourism, missions to the moon and Mars, and mining on the moon.
The Lunar Resources Registry, a private business that locates valuable resources on the moon and helps investors conduct the required exploration and extraction operations, notes: “The space race is evolving into space industrialization.”
According to NASA, “the moon holds hundreds of billions of dollars of untapped resources,” including water, helium-3 and rare earth metals used in electronics.
A close-up view of an astronaut’s footprint in the lunar soil, photographed in July 1969. (Marshall Space Flight Center/NASA)
As a group of academics researching various aspects of environmental sustainability on Earth, we are alarmed at the speed of these developments and the impacts resource exploitation will have on lunar and space environments.
There is a movement among the international geologic scientific community calling for a new epoch — the Anthropocene — reflecting the enormous extent to which human activity has altered the planet since the end of the Second World War.
Stratigraphers — geologists who study the layers of rock and sediment — look for measurable global impact of human activities in the geologic record. According to their research, the starting point for the Anthropocene has been identified as beginning in the 1950s, and the fallout from nuclear testing.
To shock humankind into preventing the extensive destruction in space that we have wrought on Earth, it may be effective to add a “lunar Anthropocene” to the moon’s geologic time scale.
The case for a lunar Anthropocene is interesting. It can be argued that since the first human contact with the moon’s surface, we have seen anthropogenic impact. This impact is likely to increase dramatically. This is presented as justification for a new geologic epoch for the moon.
An image captured immediately after the first atomic explosion in Alamogordo, N.M., on July 16, 1945. The presence of nuclear traces of the fallout from the initial nuclear explosions is claimed to mark the beginning of the Anthropocene. (Shutterstock)
This new “human epoch” is hotly debated among stratigraphers as well as researchers in other disciplines. For humanities researchers and artists, the importance of the Anthropocene lies in the power the concept has to evoke human responsibility for bringing the Earth’s system to a tipping point.
In The Shock of the Anthropocene, historians Christophe Bonneuil and Jean-Baptiste Fressoz argue that the new human epoch entails recognizing that technoscientific advances — which have driven socio-political economies relying on extractivism, consumption and waste — have led to the extent of damage we measure on Earth at present.
For millenia, most societies understood the importance of their relationship with the natural world for survival. But industrialization and the endlessly growing economy in developed countries has destroyed this relationship.
For example, trees used to be respected for providing timber, food, shade and more. But our industrial growth changed all that; in the past 100 years, more trees have been cut than had been felled in the preceding 9,000 years.
And now the Anthropocene, this age of human impact, is also arriving on the moon.
NASA estimates there are already 227,000 kilos of human garbage littering the moon, mostly from space explorations, including moon buggies and other equipment, excrement, statues, golf balls, human ashes and flags, among other objects.
An increasing number of moon missions and extracting resources from the moon could destroy lunar environments. This mirrors what has happened on our planet: humans have used this collection of “natural resources” and produced enough waste and degradation to bring us to the current sixth mass extinction precipice.
With the Artemis missions, NASA is planning to reestablish a human presence on the moon.
Our throwaway society leads to not only habitat destruction on Earth, but also now on the moon and in space. We must rethink what we really need. Without a fully functional Earth system, including biodiversity and nature’s contribution to life, we will be unable to survive.
If the intent is to issue a word of caution and pre-emptively shock and elicit a feeling of responsibility on the part of those actors likely to impact the moon’s surface, it may very well be the right time to name a lunar Anthropocene. This may help prevent the kind of extensive and careless destruction we have caused and continue to witness on Earth.
Christine Daigle, Professor of Philosophy, Brock University; Jennifer Ellen Good, Associate Professor and Chair, Communication, Popular Culture and Film, Brock University, and Liette Vasseur, Professor, Biological Sciences, Brock University
This article is republished from The Conversation under a Creative Commons license. Read the original article.
Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com.
As a toxicologist, I study the effects of drugs and environmental contaminants on human health. As part of my work, I rely on various health-related biomarkers, many of which are measured using conventional blood tests.
Understanding what common blood tests are intended to measure can help you better interpret the results. If you have results from a recent blood test handy, please follow along.
Blood samples go through several processing steps after they’re drawn.
Depending on the lab that analyzed your sample, the results from your blood test may be broken down into individual tests or collections of related tests called panels. Results from these panels can allow a health care professional to recommend preventive care, detect potential diseases and monitor ongoing health conditions.
For each of the tests listed in your report, there will typically be a number corresponding to your test result and a reference range or interval. This range is essentially the upper and lower limits within which most healthy people’s test results are expected to fall.
Sometimes called a normal range, a reference interval is based on statistical analyses of tests from a large number of patients in a reference population. Normal levels of some biomarkers are expected to vary across a group of people, depending on their age, sex, ethnicity and other attributes.
So, separate reference populations are often created from people with a particular attribute. For example, a reference population could comprise all women or all children. A patient’s test value can then be appropriately compared with results from the reference population that fits them best.
Reference intervals vary from lab to lab because each may use different testing methods or reference populations. This means you might not be able to compare your results with reference intervals from other labs. To determine how your test results compare with the normal range, you need to check the reference interval listed on your lab report.
If you have results for a given test from different labs, your clinician will likely focus on test trends relative to their reference intervals and not the numerical results themselves.
There are numerous blood panels intended to test specific aspects of your health. These include panels that look at the cellular components of your blood, biomarkers of kidney and liver function, and many more.
Rather than describe each panel, let’s look at a hypothetical case study that requires using several panels to diagnose a disease.
In this situation, a patient visits their health care provider for fatigue that has lasted several months. Numerous factors and disorders can result in prolonged or chronic fatigue.
Based on a physical examination, other symptoms and medical history, the health practitioner suspects that the patient could be suffering from any of the following: anemia, an underactive thyroid or diabetes.
Blood tests provide clinicians with more information to guide diagnoses and treatment decisions. FluxFactory/E+ via Getty Images
Blood tests would help further narrow down the cause of fatigue.
Anemia is a condition involving reduced blood capacity to transport oxygen. This results from either lower than normal levels of red blood cells or a decrease in the quantity or quality of hemoglobin, the protein that allows these cells to transport oxygen.
A complete blood count panel measures various components of the blood to provide a comprehensive overview of the cells that make it up. Low values of red blood cell count, or RBC, hemoglobin, or Hb, and hematocrit, or HCT, would indicate that the patient is suffering from anemia.
Hypothyroidism is a disorder in which the thyroid gland does not produce enough thyroid hormones. These include thyroid-stimulating hormone, or TSH, which stimulates the thyroid gland to release two other hormones: triiodothyronine, or T3, and thyroxine, or T4. The thyroid function panel measures the levels of these hormones to assess thyroid-related health.
Diabetes is a disease that occurs when blood sugar levels are too high. Excessive glucose molecules in the bloodstream can bind to hemoglobin and form what’s called glycated hemoglobin, or HbA1c. A hemoglobin A1c test measures the percentage of HbA1c present relative to the total amount of hemoglobin. This provides a history of glucose levels in the bloodstream over a period of about three months prior to the test.
Providing additional information is the basic metabolic panel, or BMP, which measures the amount various substances in your blood. These include:
With results from each of these panels, the health professional would assess the patient’s values relative to their reference intervals and determine which condition they most likely have.
Understanding the purpose of blood tests and how to interpret them can help patients partner with their health care providers and become more informed about their health.
Brad Reisfeld, Professor of Chemical and Biological Engineering, Biomedical Engineering, and Public Health, Colorado State University
This article is republished from The Conversation under a Creative Commons license. Read the original article.
CLPS will send science payloads to the Moon in conjunction with the Artemis program’s crewed missions.
NASA buys space on these landers for science payloads to fly to the Moon, and the companies design, build and insure the landers, as well as contract with rocket companies for the launches. Unlike in the past, NASA is one of the customers and not the sole driver.
The first two CLPS payloads are scheduled to launch during the first two months of 2024. There’s the Astrobotics payload, which launched Jan. 8 before experiencing a fuel issue that cut its journey to the Moon short. Next, there’s the Intuitive Machines payload, with a launch scheduled for mid-February. NASA has also planned a few additional landings – about two or three per year – for each of the next few years.
I’m a radio astronomer and co-investigator on NASA’s ROLSES program, otherwise known as Radiowave Observations at the Lunar Surface of the photoElectron Sheath. ROLSES was built by the NASA Goddard Space Flight Center and is led by Natchimuthuk Gopalswamy.
The ROLSES instrument will launch with Intuitive Machines in February. Between ROLSES and another mission scheduled for the lunar far side in two years, LuSEE-Night, our teams will land NASA’s first two radio telescopes on the Moon by 2026.
The Moon – particularly the far side of the Moon – is an ideal place to do radio astronomy and study signals from extraterrestrial objects such as the Sun and the Milky Way galaxy. On Earth, the ionosphere, which contains Earth’s magnetic field, distorts and absorbs radio signals below the FM band. These signals might get scrambled or may not even make it to the surface of the Earth.
On Earth, there are also TV signals, satellite broadcasts and defense radar systems making noise. To do higher sensitivity observations, you have to go into space, away from Earth.
The Moon is what scientists call tidally locked. One side of the Moon is always facing the Earth – the “man in the Moon” side – and the other side, the far side, always faces away from the Earth. The Moon has no ionosphere, and with about 2,000 miles of rock between the Earth and the far side of the Moon, there’s no interference. It’s radio quiet.
For our first mission with ROLSES, launching in February 2024, we will collect data about environmental conditions on the Moon near its south pole. On the Moon’s surface, solar wind directly strikes the lunar surface and creates a charged gas, called a plasma. Electrons lift off the negatively charged surface to form a highly ionized gas.
This doesn’t happen on Earth because the magnetic field deflects the solar wind. But there’s no global magnetic field on the Moon. With a low frequency radio telescope like ROLSES, we’ll be able to measure that plasma for the first time, which could help scientists figure out how to keep astronauts safe on the Moon.
When astronauts walk around on the surface of the Moon, they’ll pick up different charges. It’s like walking across the carpet with your socks on – when you reach for a doorknob, a spark can come out of your finger. The same kind of discharge happens on the Moon from the charged gas, but it’s potentially more harmful to astronauts.
Our team is also going to use ROLSES to look at the Sun. The Sun’s surface releases shock waves that send out highly energetic particles and low radio frequency emissions. We’ll use the radio telescopes to measure these emissions and to see bursts of low-frequency radio waves from shock waves within the solar wind.
We’re also going to examine the Earth from the surface of the Moon and use that process as a template for looking at radio emissions from exoplanets that may harbor life in other star systems.
Magnetic fields are important for life because they shield the planet’s surface from the solar/stellar wind.
In the future, our team hopes to use specialized arrays of antennas on the far side of the Moon to observe nearby stellar systems that are known to have exoplanets. If we detect the same kind of radio emissions that come from Earth, this will tell us that the planet has a magnetic field. And we can measure the strength of the magnetic field to figure out whether it’s strong enough to shield life.
The Lunar Surface Electromagnetic Experiment at Night, or LuSEE-Night, will fly in early 2026 to the far side of the Moon. LuSEE-Night marks scientists’ first attempt to do cosmology on the Moon.
LuSEE-Night is a novel collaboration between NASA and the Department of Energy. Data will be sent back to Earth using a communications satellite in lunar orbit, Lunar Pathfinder, which is funded by the European Space Agency.
Since the far side of the Moon is uniquely radio quiet, it’s the best place to do cosmological observations. During the two weeks of lunar night that happen every 14 days, there’s no emission coming from the Sun, and there’s no ionosphere.
We hope to study an unexplored part of the early universe called the dark ages. The dark ages refer to before and just after the formation of the very first stars and galaxies in the universe, which is beyond what the James Webb Space Telescope can study.
During the dark ages, the universe was less than 100 million years old – today the universe is 13.7 billion years old. The universe was full of hydrogen during the dark ages. That hydrogen radiates through the universe at low radio frequencies, and when new stars turn on, they ionize the hydrogen, producing a radio signature in the spectrum. Our team hopes to measure that signal and learn about how the earliest stars and galaxies in the universe formed.
There’s also a lot of potential new physics that we can study in this last unexplored cosmological epoch in the universe. We will investigate the nature of dark matter and early dark energy and test our fundamental models of physics and cosmology in an unexplored age.
That process is going to start in 2026 with the LuSEE-Night mission, which is both a fundamental physics experiment and a cosmology experiment.
Jack Burns, Professor of Astrophysical and Planetary Sciences, University of Colorado Boulder
This article is republished from The Conversation under a Creative Commons license. Read the original article.
