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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
May 14, 2026
May 14, 2026 A daily multivitamin may help slow biological aging, according to researchers studying older adults in a large clinical trial. After two years, participants taking multivitamins showed slower aging in several DNA-based “epigenetic clocks,” with ...
May 14, 2026 Scientists analyzing the genomes of thousands of people across Japan discovered evidence for a previously overlooked third ancestral group, challenging the long-accepted “dual origins” theory. The newly identified ancestry appears linked to the ...
May 13, 2026 UC Davis researchers created brand-new psychedelic-like compounds by shining UV light on amino acid-based molecules. These compounds activated key serotonin receptors tied to brain plasticity and mental health benefits, but surprisingly did not ...
May 13, 2026 A huge long-term study found that drinking two to three cups of coffee a day was linked to a much lower risk of dementia, especially before age 75. Researchers say caffeine may help keep brain cells active while reducing inflammation and harmful ...
May 13, 2026 Researchers have uncovered unexpectedly high levels of silicone-based pollutants called methylsiloxanes floating through the atmosphere across cities, rural regions, and even forests. Much of the pollution appears to come from vehicle emissions, ...
May 13, 2026 The little pauses, “ums,” and moments when you struggle to find the right word may reveal far more about your brain than anyone realized. Researchers discovered that everyday speech patterns are closely tied to executive function — the mental ...
May 12, 2026 Scientists at UBC Okanagan have uncovered how plants produce mitraphylline, a rare natural compound with promising anti cancer potential. The team identified two enzymes that work together to build the molecule’s unusual twisted structure, solving ...
May 12, 2026 Scientists at the University of Maryland, Baltimore County, have uncovered a crucial trick used by enteroviruses—the group behind diseases like polio, myocarditis, encephalitis, and even the common cold—to reproduce inside human cells. The team ...
May 12, 2026 Researchers found a new way to kill harmful “zombie” cells that linger after chemotherapy and help cancers become more aggressive. These senescent cells survive by relying on a protective protein called GPX4, even while sitting on the edge of a ...
May 12, 2026 As blood stem cells age, their lysosomes become overactive and damaged, triggering inflammation and weakening the body’s ability to regenerate healthy blood and immune cells. By calming this ...
May 12, 2026 A four-week diet change was enough to make some older adults appear biologically younger in a new University of Sydney study. Participants who reduced fat intake or shifted toward more plant-based ...
May 12, 2026 Scientists at McGill University have uncovered a hidden molecular “switch” that turns on a powerful calorie-burning system in brown fat — the body’s heat-generating fat linked to metabolism and weight control. The breakthrough centers on ...
Latest Headlines
updated 12:56 pm ET
May 11, 2026 Staying strong may be one of the biggest secrets to living longer — especially for older women. A major study of more than 5,000 women found that simple signs of muscle strength, like a firm hand ...
May 11, 2026 An ancient Chinese exercise routine may be just as powerful as a daily brisk walk for lowering blood pressure — without equipment, gyms, or intense workouts. In a major clinical trial, adults with ...
May 11, 2026 Researchers say fructose is not just “empty calories” — it may actively push the body toward fat storage and metabolic disease. A new review ...
May 11, 2026 A new international analysis suggests there may be a surprisingly simple secret to keeping weight off after dieting: walking about 8,500 steps a day. Researchers found that people who boosted their ...
May 11, 2026 A major new analysis suggests semaglutide (Ozempic, Wegovy) works remarkably well in adults over 65, helping many lose substantial amounts of weight while improving heart and metabolic health. ...
May 10, 2026 Ultra-processed foods may be doing far more damage than many people realize. A major new European cardiology report warns that people who eat the ...
May 10, 2026 Scientists at the University of Rochester pulled off a remarkable experiment: they transferred a longevity-related gene from the famously long-lived naked mole rat into mice, and the mice ended up ...
May 10, 2026 Scientists have uncovered a hidden “stop-scratching” signal in the nervous system that tells your brain when enough scratching is enough. The discovery centers on a molecule called TRPV4, which ...
May 9, 2026 Rebooting the gut microbiome with bacteria from youth may help stop aging-related liver damage and even prevent liver cancer, according to new research in mice. Older mice that received their own ...
May 9, 2026 Researchers have developed a stem cell-based model of the human intestine that may transform how new IBD treatments are discovered. After testing thousands of compounds, they identified glycyrrhizin ...