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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
August 30, 2026
Aug. 30, 2026 Omega-3 and low-dose aspirin matched the effectiveness of antibiotics in a year-long study of patients with severe gum disease, with both approaches helping about 58% reach the treatment goal. The unexpected result could point to a new way to treat ...
Aug. 30, 2026 Adults aged 40 and older performed about 12% faster on a test of executive function after using a HEPA air purifier at home for one month. The findings suggest that cleaner indoor air could offer a simple way to help protect the brain from the ...
Aug. 30, 2026 Researchers have produced a form of Spirulina containing biologically active vitamin B12 at levels comparable to beef. By carefully controlling the light used to grow the algae, they overcame a major problem with conventional Spirulina, which mainly ...
Aug. 29, 2026 CAR T-cell therapy dramatically reduced disease activity in six people with severe rheumatoid arthritis that had resisted other treatments, with three achieving medication-free remission. The treatment may work by clearing out harmful immune cells ...
Aug. 29, 2026 A ketogenic diet outperformed Mediterranean and low-fat diets in several measures of metabolic health during a clinical trial involving people with obesity, prediabetes, and fatty liver disease. All three groups lost about 10% of their body weight, ...
Aug. 29, 2026 Dogs and humans may have more in common when it comes to aging than scientists realized. Researchers with the Dog Aging Project found that patterns of small molecules in dogs’ blood were linked to longer or shorter lifespans in remarkably similar ...
Aug. 29, 2026 People with chronic insomnia who used melatonin long term had a roughly 90% higher risk of developing heart failure over five years, according to a large preliminary study. The findings do not prove melatonin causes heart problems, but they raise ...
Aug. 28, 2026 Frequent micro-awakenings during sleep were linked to higher genetic risk for Alzheimer’s in healthy middle-aged adults who had no symptoms. The discovery raises the possibility that subtle changes during sleep could offer an early warning signal ...
Aug. 28, 2026 Scientists have identified a protein that acts like a brake on the nervous system’s ability to repair damaged connections. Blocking AHR helped injured nerve fibers regrow and improved movement and sensation in mice with nerve or spinal cord ...
Aug. 28, 2026 Scientists have created light-activated drugs that helped blind mice perceive light again and restored visually guided behavior without gene therapy, implants, or specialized lighting. Even more intriguingly, two of the most promising compounds ...
Aug. 28, 2026 A popular vanilla flavoring in e-cigarettes may interfere with some of the earliest steps of human development. In lab experiments, vanillin caused embryonic stem cells to lose their ability to develop normally and pushed them toward forming only ...
Aug. 28, 2026 Every one of 212 plant-based meat alternatives and drinks tested in the UK contained at least one naturally occurring fungal toxin, though concentrations remained below recommended EU guideline ...
Latest Headlines
updated 12:56 pm ET
Aug. 27, 2026 Ultra-processed foods make up a huge share of the American diet, and new research suggests they may carry another serious health risk for men. In a nationally representative study of more than 17,000 ...
Aug. 27, 2026 The belief that huge doses of vitamin C can ward off colds was popularized more than 50 years ago by Nobel Prize winner Linus Pauling. Since then, larger studies have found that vitamin C does not ...
Aug. 27, 2026 Scientists created smart nanoparticles that can both illuminate hidden glioblastoma cells during surgery and destroy microscopic cancer left behind afterward. In mice, the treatment prevented ...
Aug. 27, 2026 Researchers discovered a brain-based “brake” that can shut down chronic nerve pain in mice by calming an overactive pain circuit. Targeting this system more precisely could one day lead to ...
Aug. 26, 2026 Moderate calorie restriction lowered an immune protein called C3 that appears to help drive chronic inflammation as the body ages. Blocking the same ...
Aug. 26, 2026 Britain’s postwar sugar rationing created a rare natural experiment that let researchers examine how early sugar exposure might affect health decades later. People who experienced more rationing ...
Aug. 26, 2026 A compound found in turmeric may help protect blood vessels from some of the damage caused by Type 1 diabetes. In rats, curcumin reduced inflammation, improved cellular signaling, and restored ...
Aug. 26, 2026 A wavelength of light largely missing from indoor LEDs may play an important role in protecting developing eyes from nearsightedness. Researchers found that indigo light completely prevented myopia ...
Aug. 26, 2026 Early-life stress may physically alter how DNA is packaged in the brain, leaving stress-related genes primed to activate more easily years later. In mice, researchers were able to block this effect, ...
Aug. 25, 2026 A low-carb diet may raise LDL cholesterol much more sharply in people who are genetically predisposed to high cholesterol, particularly when they consume lots of saturated fat. The findings could ...