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Human genome
The human genome is the genome of Homo sapiens. It is made up of 23 chromosome pairs with a total of about 3 billion DNA base pairs. There are 24 distinct human chromosomes: 22 autosomal chromosomes, plus the sex-determining X and Y chromosomes. Chromosomes 1-22 are numbered roughly in order of decreasing size. Somatic cells usually have one copy of chromosomes 1-22 from each parent, plus an X chromosome from the mother, and either an X or Y chromosome from the father, for a total of 46. There are an estimated 20,000-25,000 human protein-coding genes. The estimate of the number of human genes has been repeatedly revised down from initial predictions of 100,000 or more as genome sequence quality and gene finding methods have improved, and could continue to drop further.
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Health & Medicine News
September 26, 2026
Sep. 26, 2026 A new analysis suggests mammograms may lead to far less breast cancer overdiagnosis than some earlier studies indicated. Researchers reexamined all eight major randomized screening trials and ...
Sep. 26, 2026 Researchers found that scented cleaners can react with ozone indoors to create billions or trillions of invisible nanoparticles that can penetrate deep into the lungs. The pollution forms within minutes and, in some cases, may produce an inhaled ...
Sep. 26, 2026 Tirzepatide, sold as Mounjaro and Zepbound, activated calorie-burning brown fat in obese mice, revealing a potential metabolic effect beyond appetite suppression. If confirmed in humans, the finding could help explain the drug’s powerful benefits ...
Sep. 25, 2026 Scientists discovered rare flavoalkaloids in Cannabis leaves for the first time, along with dozens of other phenolic compounds that had never been reported in the plant. The findings suggest that ...
Sep. 25, 2026 A major analysis suggests Phelan-McDermid syndrome, a genetic disorder closely linked to autism, may affect about 1 in 7,300 people and more than 45,000 Americans. Researchers warn that thousands of ...
Sep. 25, 2026 Researchers used CRISPR to remove CD33 from donor stem cells, potentially giving doctors a way to attack aggressive blood cancers without destroying the healthy cells patients need after a ...
Sep. 24, 2026 A magnet-producing bacterium extended the average lifespan of C. elegans worms by more than 43% while helping protect their neurological and intestinal health. Researchers traced much of the effect to suppression of ferroptosis, a damaging form of ...
Sep. 24, 2026 Scientists discovered a surprising backup system that lets mammalian cells make the essential amino acid cysteine even when the pathways once considered indispensable are disabled. The same survival ...
Sep. 24, 2026 A 70-year-old leukemia drug is still revealing new secrets. Researchers found that removing a protein called NUDT5 protected cells from the drug, even though simply blocking the protein had little effect. The unexpected result points to a hidden ...
Sep. 24, 2026 A newly identified breakdown in communication between nerves and muscles could help explain why people lose strength as they age. Researchers were able to improve muscle strength in an animal model by targeting a key protein, raising hopes that some ...
Sep. 23, 2026 A large study tracking more than 95,000 people suggests that how you sleep may be linked to your risk of developing dozens of diseases. People who spent more time in REM sleep had lower risks of 83 conditions, including dementia, heart failure, and ...
Sep. 23, 2026 Children taking GLP-1 medications (such as Victoza, Saxenda, Trulicity, and Ozempic) for weight loss, prediabetes, or type 2 diabetes may face an overlooked risk: nutritional deficiencies. A new ...
Latest Headlines
updated 12:56 pm ET
Sep. 23, 2026 A major Swedish study of 3.7 million people has found that rare TORCH infections passed from a pregnant woman to the fetus are linked to much higher risks of autism and intellectual disability later ...
Sep. 23, 2026 A topical drug that removes aging, damaged cells helped older mice heal skin wounds significantly faster. The treatment appeared to reactivate repair pathways involved in inflammation, collagen ...
Sep. 22, 2026 A new experimental drug called CS18 may help break through cancer drug resistance by disabling several of the defenses tumors use to survive treatment. It strengthened existing therapies, restored ...
Sep. 22, 2026 Caffeine may make sleep less restorative even when you fall asleep normally and stay in bed for eight hours, with EEG recordings revealing fewer of the slow brain waves associated with deep sleep. ...
Sep. 22, 2026 A minimally invasive procedure called genicular artery embolization could offer a new middle ground between conservative treatments and knee replacement for osteoarthritis. By blocking tiny blood ...
Sep. 21, 2026 Researchers have found evidence that long COVID may damage dopamine releasing neurons in the brain, potentially explaining persistent fatigue, low motivation, slowed movement, and memory ...
Sep. 21, 2026 Stem cell transplants helped regenerate stroke-damaged brain tissue in mice, producing new neurons and restoring lost motor function. The treatment also improved blood vessels, inflammation, and the ...
Sep. 21, 2026 A large study suggests the cardiovascular benefits of GLP-1 drugs such as Ozempic, Wegovy, Mounjaro, and Zepbound can disappear surprisingly quickly when treatment stops. After two years off the ...
Sep. 21, 2026 A new needle-thin brain implant can record neural activity, deliver drugs, and stimulate multiple brain regions using a single flexible fiber. ...
Sep. 21, 2026 Chronic inflammation tied to stress, lifestyle, mental health, and socioeconomic conditions may silently change the heart for years before any symptoms appear. People with the highest inflammation ...