Roughly 1 in every 4,300 individuals in the US has mitochondrial disease

The first child born via mitochondrial replacement therapy was born in 2016

The healthy baby boy's mother carried genes for a rare mitochondrial disease called Leigh syndrome and after multiple miscarriages the family opted to try the controversial procedure. It was conducted by a US doctor in Mexico. The procedure is prohibited in the United States.

Without 3-parent IVF, women carrying faulty mitochondrial DNA have few options for children

Women who are carriers of mitochondrial diseases that wish to have children without those conditions cannot be biological parents without three-parent IVF. The alternatives are to adopt or have a child via egg donation.

More than 5 million Americans have more than one autoimmune disease

Overall, about 4.6% of the US population—15 million people—have an autoimmune condition. Some common examples include rheumatoid arthritis, psoriasis, type 1 diabetes, Grave's disease, and autoimmune thyroiditis.

Mitochondria—only inherited from mothers in most animals—have their own DNA

Mitochondrial DNA, or mtDNA, typically takes the shape of a circle and contains genes that code for proteins essential to the production of energy-containing molecules called ATP. When mitochondria fuse, the mixing of healthy and damaged mtDNA helps alleviate the effects of mutations that may have occurred during mitochondrial division or environmental interactions.

Someone suffers from a stroke every 40 seconds

Every 40 seconds, someone in the US experiences a stroke—and every minute without treatment destroys millions of brain cells. This explainer breaks down the two main types of strokes, their risk factors, and how early detection could change outcomes in the future.

Chagas disease can be transmitted to a fetus during pregnancy

Researchers estimate that 63 to 315 cases of congenital Chagas disease occur annually in the US. Roughly 20 to 30 percent of all Chagas disease cases will progress to cardiac or gastrointestinal disease.

Common genetic disorders

As research continues, it's clear that disease and genetics go hand in hand. Here's a selection of 50 National Human Genome Research Institute (NHGRI) articles providing basic information on genetic, orphan, and rare diseases caused by mutations in DNA sequences, whether inherited from parents or brought about by outside factors.

Rodent evidence is mounting that dysfunctional mitochondria may be a cause of Parkinson's

Though researchers have long observed mitochondrial malfunction in Parkinson's patients, it has remained unclear whether faulty mitochondria cause the disease or are casualties of it. Rodent research published in 2025 adds further weight to the idea that it's causative.

Each day, about 60 US pregnancies end in stillbirth

This online memorial for families who experienced the unexpected death of a fetus 20 weeks or older is the result of ProPublica reporters inviting 60 families to share their baby's name and answer some questions about their unfulfilled wishes for their children. About 21,000 babies are stillborn in the US annually. About the same number of children die in the US during their first year of life.

CRISPR can't fix faulty mitochondria

Gene editing via CRISPR could theoretically fix many issues in biology, but editing the mitochondrial genome has remained challenging. In recent years, there has been some progress reaching these cellular powerhouses. (Some users may experience a paywall.)

Motocross is the deadliest organized sport for US kids

At least 158 participants under the age of 20 have been killed on dirt bikes since 2000, roughly six on average per year (seven times the death rate of tackle football). Observers note risks come from mixing ages and lacking warning systems during crashes.

Low cell division rates in heart cells make heart cancer particularly rare

The heart's location in the chest also offers protection from external cancer-causing factors. The disease affects about 3 in every 10,000 people, though most cases arise from metastasis from other body parts.

1 in 6 Americans get food poisoning each year

The US federal government estimates there are about 48 million cases of foodborne illness in the country annually, resulting in as many as 3,000 deaths and 128,000 hospitalizations. Food poisoning puts those with weakened immune systems, the elderly, pregnant people, and young children at particularly high risk. This chart of common disease-causing pathogens highlights common threats and details about them, including likely food sources.

Roughly 1 in 125 people have autism spectrum disorder globally

The disorder has been increasingly diagnosed as its definition has grown broader and as clinicians have become more adept at identifying it—with some estimates suggesting the figures are much higher. These figures include people across the spectrum, some of whom live mostly independent lives, while others require life-long care and assistance.

About 2,000 US babies are born annually without some portion of their limbs, potentially leading to a lifetime of pricey prosthetics.

Neglected tropical diseases affect more people than the population of Europe

This group of conditions, which includes hookworm, sickens roughly one in seven people on the planet—a tally which dwarfs Europe's population of roughly 450 million. International cooperation and donations are helping to control some of these illnesses, which can be caused by parasites, viruses, and bacteria. They're all treatable or preventable, but primarily occur among poor, isolated communities that may not receive adequate care.

Bipolar disorder, which is characterized by extreme mood swings, affects nearly 3% of the US population

There are two types of this disorder. Bipolar 1 features a significant manic episode—abnormally elevated mood and frantic energy—followed by repeated depression, while Bipolar 2 vacillates between depressive episodes and hypomania, a milder form of mania, but not a full mania. Listen to this podcast as experts explain the condition.

Sickle cell trait can put people at elevated risk of heat-related illness

This hereditary blood disorder affects the shape and function of red blood cells. A US military study found that among recruits the incidence rate of exertional heat-related illness was 48% higher among those who had sickle cell trait as compared to those without. Easing into intense exercise and gradually increasing exertional frequency and intensity is recommended.

See the incidence of Lyme disease across all 50 states in 2023

The US states with the highest rate of Lyme disease—meaning cases per 100,000 people—were Rhode Island, Vermont, and Maine, in 2023. Rhode Island had 260 cases per 100,000 people, based on cases reported to the US Centers for Disease Control and Prevention. (Some users may encounter a paywall.)

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

736,900 cochlear implants had been implanted by 2020 worldwide

In the United States, roughly 118,100 devices had been implanted in adults by that point and 65,000 in children. These estimated figures come from the US Food and Drug Administration, which first approved cochlear implants for adults experiencing hearing loss in the mid-1980s, and collected reports from cochlear implant manufacturers approved for the US market.

Why death is caused by a dearth of ATP

Though people die from many causes, this video makes the case that a lack of adenosine triphosphate production in the body is what kills almost all of us. Without ATP, physiological processes grind to a halt, and organs stop functioning.

There may be 500,000 additional malaria deaths by 2050

Research published in the journal Nature in January 2026 estimates that by 2050, climate change may trigger more than half a million additional malaria deaths and over 100 million additional malaria cases. The work is based on climate change projections and available disease information and did not incorporate new vaccine uptake.

Bone marrow generates roughly 500 billion new blood cells each day

Some of our bones are stuffed to the brim with a fatty, jam-like substance called marrow. Bone marrow comes in yellow and red, with the latter responsible for producing new blood cells, and has become critical in treating diseases like leukemia.

Secondary complications from measles in children range across the whole body

The most serious effects of a measles infection, particularly in young children, come from its attack on the immune system. This leaves the whole body vulnerable to follow-on diseases, with some of the most serious including respiratory conditions, encephalitis, and more.

US macular degeneration burden is based on statistical modeling and Medicare claims

Prevalence estimates for age-related macular degeneration in the US are usually based on the Vision and Eye Health Surveillance System. Disease numbers are generated using Bayesian meta-regression (a type of statistical modeling), which pulls together information from multiple sources, including Medicare claims.

The human brain only uses 5% more energy during active tasks versus resting

Despite only being 2% of the weight of a human body, the average adult brain consumes 20% of its energy, with the majority of it spent on maintaining homeostasis—the stable equilibrium conditions of temperature, acidity, blood sugar, and other properties in the body. For infants, the consumption is closer to 50%.

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

Between 10 million and 50 million people in the US develop rashes from poison ivy, poison sumac, and poison oak each year.

About 12.5% of US adults experience a phobia in their lifetime, a diagnosis that hinges on the intense fear interfering with daily life and persisting for at least six months.

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

Human-to-human transmission of hantavirus remains extremely rare, so the 2026 hantavirus cruise ship outbreak doesn't mean we're facing a COVID-style pandemic risk.

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

View the ten deadliest tornadoes in US history.

Ebola infects and disables immune cells, triggering a cascade of events that leads to small blood clots throughout the body, weakening blood vessels and interrupting blood flow to key organs.

Fireworks-related ER visits are on the rise—in 2024, they increased by 52% as compared to the prior year.

Calculate how much of your tax dollars go to each federal program based on your income, filing status, and number of children

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

In 1939, baseball star Lou Gehrig delivered his inspirational 'Luckiest Man' speech after retiring due to the health condition that now bears his name.

Children are now three times more likely to say they want to be a YouTuber when they grow up than an astronaut, with some even attending 'YouTube camps' that teach kids how to create content for the platform.

While atoms are normally made of protons, neutrons, and electrons, exotic ones have been built with antimatter—alternate versions of normal matter that live for fractions of a second and are about a billion times as rare.

Despite being favored by 87% of Americans, Congress does not have term limits.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

The US dollar is the most widely circulated currency in the world, and is involved in nearly 90% of global transactions

The 1987 Nintendo video game 'Stadium Events' isn't known for being particularly fun, but its scarcity has made it a highly sought-after item that has sold for up to $35K at auction.

Take a 3D tour of the Hajj, Islam's annual pilgrimage to Mecca, undertaken by more than 1.5 million Muslims each year.

US intelligence allegedly pursued more than 600 schemes to assassinate Cuban revolutionary Fidel Castro.