Scientists uncover possible missing link between 'mono' virus and multiple sclerosis
When you buy through links on our articles, Future and its syndication partners may earn a commission.
For years, scientists have known that the virus behind "mono" dramatically raises the risk of multiple sclerosis (MS), a disease in which the immune system attacks nerve cells. But while most people are exposed to the mono virus by adulthood, only a few develop MS, raising the question of why.
Now, researchers have uncovered a possible reason why most people infected with the mono virus never develop MS: a specific immune-system gene may mediate their risk.
The mono virus — called Epstein-Barr virus (EBV) — infects more than 90% of people by adulthood, although it usually causes no symptoms. In some people, it can trigger infectious mononucleosis, better known as mono, causing fever, swollen lymph nodes and fatigue.
Despite EBV's widespread presence, very few people exposed to the virus go on to develop MS, a chronic condition that affects the brain and spinal cord. Now, scientists have identified a specific genetic variant that may help explain this disparity. They published their results April 7 in the European Journal of Neurology.
"The findings … could offer clues as to why only a small fraction of people develop MS despite the fact that over 90% of the global population are infected with EBV," Lisa Kiani, a senior editor of Nature Reviews Neurology, wrote in a summary of the study.
Related: $3 million Breakthrough Prize goes to scientists that completely changed our understanding of multiple sclerosis
The team found that people who carry a genetic variant called HLA-E*01:01 are more likely to develop MS than people without the variant, but only if they have previously had mono.
The gene HLA-E is thought to influence the immune system by interacting with white blood cells, which help defend the body against infections and abnormal cells. A 2023 study published in the journal Cell found that many people with MS have previously been infected with variants of EBV that boost production of the protein that this gene encodes. This molecule can help harmful, self-destructive cells evade detection and destruction by the immune system.
For the current study, the researchers examined data from more than 487,000 people from the UK Biobank, a biomedical database and research resource that includes data from 500,000 U.K. adults. They examined whether individuals carried the HLA-E*01:01 gene variant and reviewed their medical histories to see if they had ever been diagnosed with infectious mononucleosis.
The group also accounted for other known MS risk factors, like smoking, childhood obesity and other genetic markers. The findings showed that people with the HLA-E*01:01 variant who had previously had mono were much more likely to develop MS than those who carried the variant but never had mono, or those with a different version of the same gene.
In other words, the combination of the genetic variant and mono appeared to work together to raise the risk of developing MS. This may be because this specific version of the HLA-E gene may raise the risk of MS by weakening the immune system's ability to control EBV infection.
RELATED STORIES
—1 gene may explain 30 mysterious medical conditions
—People with this rare genetic condition can't repair damage to their DNA
—Origins of schizophrenia linked to epigenetics of the placenta
For people who carried two copies of the variant — one from each parent — and had a history of mono, these factors accounted for 65% of their risk of MS, lead study author Andrea Nova, a postdoctoral researcher at the University of Pavia, told Nature Reviews Neurology.
"This finding further supports the idea that genetic susceptibility is necessary for IM [infectious mononucleosis] to act as a risk factor for MS, and vice versa," Nova said.
The findings could play an important role in improving early detection and treatment of MS. In theory, by screening for the HLA-E*01:01 genetic variant, doctors may be able to identify people at higher risk of developing the disease down the line, especially if they've had mono. This could enable earlier diagnosis and prompt treatment, which is key to slowing long-term damage. Early intervention can significantly improve a person's overall health and quality of life.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
8 hours ago
- Yahoo
Jellyfish Lake: Palau's saltwater pool with a toxic bottom and surface waters brimming with millions of jellyfish
When you buy through links on our articles, Future and its syndication partners may earn a commission. QUICK FACTS Name: Jellyfish Lake, or "Ongeim'l Tketau" in Palauan Location: Palau, Western Pacific Coordinates: 7.161200817499221, 134.37633688402798 Why it's incredible: The lake has three layers, including one inhabited by millions of jellyfish and another containing poisonous gas. Jellyfish Lake is a pool of saltwater on Eil Malk island in Palau that is brimming with golden jellyfish — a subspecies not found anywhere else on Earth. The lake typically houses around 5 million jellyfish, according to the Coral Reef Research Foundation (CRRF) — although there have been years, including 2005, when the number of jellies exceeded 30 million. Jellyfish Lake is highly stratified, meaning it is separated into distinct layers. Golden jellyfish inhabit the top layer, which extends from the surface down to about 43 feet (13 meters) deep. Between 43 and 50 feet (13 to 15 m) deep, the lake contains pink bacteria that prevents light and oxygen from reaching the bottom layer of the lake, which sits between 50 and 100 feet (15 to 30 m) deep. The lake is connected to the ocean through small cracks in Eil Malk's limestone rock, but it is nevertheless considered an isolated ecosystem, according to CRRF learning resources. Jellyfish Lake formed toward the end of the last ice age, roughly 12,000 years ago, due to ice melt and sea level rise. Sea water filled depressions in Palau's islands and elsewhere, creating three types of lakes: stratified lakes, such as Jellyfish Lake; mixed lakes, which are connected to the ocean via large tunnels; and transitional lakes, which are also connected to the ocean, but via smaller tunnels. Related: 'A challenge and an opportunity for evolution': The extreme, hidden life thriving in Earth's most acidic and alkaline lakes Jellyfish Lake's pink layer exists because the conditions in that layer suit a type of bacteria that are pink in color. These bacteria create a barrier between the lake's oxygenated top layer and its oxygen-free bottom layer. This barrier bobs up and down depending on density changes in the water. The lack of oxygen beneath the pink layer is deadly for most life. What's more, plant and animal decomposition at the bottom of Jellyfish Lake releases poisonous hydrogen sulfide gas, which means only certain microbes can survive there, according to the CRRF. Jellyfish Lake's endemic golden jellyfish (Mastigias papua etpisoni) population likely evolved from a handful of spotted jellyfish (Mastigias papua) that became trapped when sea levels dropped following the lake's formation. Unique conditions inside the lake forced the jellies to adapt, leading to a new subspecies, which is named after Palau's former president, Ngiratkel Etpison. MORE INCREDIBLE PLACES —Lake Salda: The only place on Earth similar to Jezero crater on Mars —Lake Kivu: The ticking time bomb that could one day explode and unleash a massive, deadly gas cloud —Rainbow swamp: The flooded forest in Virginia that puts on a magical light show every winter Golden jellyfish have a symbiotic relationship with single-celled, photosynthetic algae that give them nutrients in exchange for a place to live. The jellyfish follow an unusual migration pattern that involves swimming towards the sun as it rises and sets, always avoiding the lake's edges where jellyfish-eating sea anemones (Entacmaea medusivora) lurk. These predatory anemones prefer the shadows, so golden jellyfish have evolved to stay in sunlit waters. Every morning, the jellies crowd along the lake's eastern shadow line, and visitors may occasionally see a "wall" of jellyfish forming underwater, according to the CRRF. While golden jellyfish have stinging cells, the sting is so mild that humans can't feel it. Visitors can safely swim in Jellyfish Lake, but people should take care not to accidentally introduce non-native species to the lake, as these can, and already do, endanger the fragile ecosystem, according to the CRRF. Discover more incredible places, where we highlight the fantastic history and science behind some of the most dramatic landscapes on Earth.
Yahoo
8 hours ago
- Yahoo
A hidden 'super-Earth' exoplanet is dipping in and out of its habitable zone
When you buy through links on our articles, Future and its syndication partners may earn a commission. A huge "super-Earth" with an extreme climate that results in it being habitable for only part of its orbit has been discovered orbiting a star 2,472 light years away. And the most remarkable thing is, it was discovered without even being directly detected. The discovery of the exoplanet, a super-Earth called Kepler-735c, is all down to something called transit timing variations, or TTVs for short. Let's set the scene. One of the primary ways of discovering exoplanets is by looking for when they transit, or pass in front of, their star. As they do so, they block a small fraction of that star's light, and, based on the size of this dip in stellar brightness, we can determine how large the transiting planet must be. Indeed, this was how the most successful exoplanet hunter so far, NASA's Kepler space telescope, discovered over 3,300 confirmed exoplanets and thousands more candidates. There are downsides to detecting exoplanets via transits, however. One is that the technique is biased toward planets on short orbits close to their star, which means they transit more often and are easier to see. Transits also require a precise alignment between the orbital plane of a planetary system and our line of sight. Even a small tilt might mean we cannot see planets on wider orbits transiting. Those unseen planets on wider orbits can still make their presence felt, however, in the form of TTVs. Ordinarily, transits are as regular as clockwork, but in some cases astronomers have noticed that a planet's transit can be delayed, or occur ahead of schedule, and that this is being caused by the gravity of other planets tugging on the transiting world. Sometimes we can see those other planets transiting as well — the seven-planet TRAPPIST-1 system is a great example. Often, though, we can't see the planet that is causing the variations, but the size and frequency of the TTVs can tell us about the orbital period and mass of these hidden worlds. One such planet that has been found to experience TTVs is Kepler-725b. It's a gas giant planet orbiting a yellow sun-like star that was discovered by the now-defunct Kepler spacecraft. "By analyzing the TTV signals of Kepler-725b, a gas giant planet with a 39.64-day period in the same system, the team has successfully inferred the mass and orbital parameters of the hidden planet Kepler-725c," Sun Leilei, of the Yunnan Observatories of the Chinese Academy of Sciences, said in a statement. Sun is the lead author of a new study revealing the existence of this hidden world. Kepler-725c's mass is quite significant — 10 times greater than the mass of Earth. This places it in the upper echelons of a type of planet called super-Earths — giant, probably rocky worlds. We don't have an example of a super-Earth in our solar system, so we don't really know what such planets are like. Planetary scientists are still grappling with theoretical models that attempt to describe the properties of super-Earth worlds. Would they be wrapped in a dense atmosphere? Could they maintain plate tectonics? How would their higher surface gravity affect the evolution of life? Definitive answers to these questions have not yet been forthcoming. Meanwhile, the planet's orbit is unusual to say the least. It is highly elliptical, with an eccentricity of 0.44. For comparison, Earth's orbit has an eccentricity of 0.0167 and is therefore close to circular; at the other extreme, an orbital eccentricity of 1 would be parabolic. Kepler-7825c's orbit is oval-shaped, meaning that at some points in its orbit it is much closer to its star than at other times. While overall Kepler-725c receives 1.4 times as much heat from its star as Earth does from the sun, this is just the average over the course of its orbit, and at times it is receiving less. If Kepler-725c has an atmosphere, then the difference in solar heating at different times in its orbit could wreak havoc on its climate. In fact, the high orbital eccentricity actually means that the exoplanet only spends part of its orbit in the habitable zone, which is a circular zone around the star at a distance where temperatures are suitable for liquid water on a planet's surface. Related Stories: — Exoplanets: Everything you need to know about the worlds beyond our solar system — Scientists discover super-Earth exoplanets are more common in the universe than we thought — Does exoplanet K2-18b host alien life or not? Here's why the debate continues Does this mean that Kepler-725c is only habitable for part of its 207.5-Earth-day year? What would happen to any life that might exist on the planet during the periods that it is outside of the habitable zone? Again, these are theoretical problems that scientists have been wrestling with, but now the existence of Kepler-725c suddenly makes them very real problems. However, because we do not see Kepler-725c transit, it will not be possible to probe its atmosphere with the James Webb Space Telescope, which uses sunlight filtered through a planet's atmosphere to make deductions about the properties and composition of that atmosphere. Fortunately, there may be more such worlds out there to study. It is expected that when the European Space Agency's PLATO (PLAnetary Transits and Oscillations of stars) spacecraft launches in 2026 as our most sensitive exoplanet-detecting mission yet, it will be able to find many more worlds through TTVs. And, unlike radial velocity and transit measurements, which tend to be biased toward finding short-period exoplanets, TTVs open a window onto planets on wider orbits that are not seen to transit. "[Kepler-725c's discovery] demonstrates the potential of the TTV technique to detect low-mass planets in habitable zones of sun-like stars," said Sun. By doing so, the TTV method will help further the search for life in the universe, if only in providing more statistics as to the numbers of habitable zone planets that are out there. The discovery of Kepler-725c was reported on Tuesday (June 3) in the journal Nature Astronomy.
Yahoo
8 hours ago
- Yahoo
Two stunning conjunctions will light up the night sky in June. Here's how to see them.
When you buy through links on our articles, Future and its syndication partners may earn a commission. Two rare twilight pairings will grace the June 2025 sky as the moon first passes close to elusive Mercury and then gets stunningly close to Mars. Mercury is typically difficult to see and the conjunction between Mars and the moon will be particularly close, so both will be special sights for skywatchers. The moon and Mercury meet-up comes as the "Swift Planet," which orbits the sun every 88 days, emerges from our star's glare into the post-sunset sky between June 21 and 30. According to NASA, Mercury will be visible just above the western horizon for 30 to 45 minutes after sunset. On Thursday (June 26), a very slim crescent moon will appear between Mercury and the two bright stars in the constellation Gemini — Pollux and Castor — causing a brief line of lights in the post-sunset night sky. On Friday (June 27), the crescent moon will be higher in the sky, just above Mercury. Precisely how low Mercury is, and how long it's observable during this period, depends on your location, so check or Stellarium. That also applies to seeing what is arguably the skywatching highlight of the month on Sunday (June 29), when amateur astronomers will get a stunning view of a 24%-illuminated crescent moon directly beneath Mars in the constellation Leo, with just 0.2 degrees (12 arcminutes) separating them. The two worlds will appear so close that a fingertip held at arm's length will cover them. RELATED STORIES —The 10 best stargazing events of 2025 —Full moons of 2025: When is the next full moon? —Have all 8 planets ever aligned? The sight will be high in the western sky and easily visible without any equipment, but the two celestial bodies will be so close that they'll fit into the same field of view of a telescope. Although it's rare to see the moon and Mercury together in the night sky, and the closeness of the moon and Mars is also unusual, conjunctions between our natural satellite and planets are not uncommon. Planets orbit the sun on more or less the same plane, called the ecliptic. It's the same path the sun takes through the daytime sky as seen from Earth. The moon's orbit of Earth isn't quite the same, but its rather wobbly path differs from the ecliptic by only five degrees. Twice a month, the moon crosses the ecliptic (hence the name, because that sometimes causes solar and lunar eclipses), so it can come particularly close to a planet as seen from our terrestrial viewpoint. The next significant close planetary conjunction will be the meeting of Venus and Jupiter in the pre-dawn hours of Aug. 12, when the two brightest planets will form a dazzlingly close pair. Originally published on Live Science.
