Reference Terms
from Wikipedia, the free encyclopedia
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.
Related Stories
1
2
Health & Medicine News
October 8, 2025
Oct. 7, 2025 — Ancient humans crossing the Bering Strait into the Americas carried more than tools and determination—they also carried a genetic legacy from Denisovans, an extinct human relative. A new study reveals that a mysterious gene called MUC19, inherited ...
Oct. 7, 2025 — Scientists have discovered that bacteria living inside tumors can produce a molecule that fights cancer and enhances chemotherapy. The molecule, called 2-methylisocitrate (2-MiCit), was found to make colorectal cancer cells more vulnerable to ...
Oct. 7, 2025 — Scientists have discovered that DMT, a natural compound found in plants and even the human brain, can dramatically reduce brain damage caused by stroke. The psychoactive molecule, long known for its hallucinogenic effects, restored the blood-brain ...
Oct. 7, 2025 — Researchers in Japan have pinpointed a biological cause of Long COVID brain fog using advanced PET brain imaging. They discovered widespread increases in AMPA receptor density linked to cognitive ...
Oct. 7, 2025 — Addiction often isn’t about chasing pleasure—it’s about escaping pain. Researchers at Scripps Research have discovered that a tiny brain region called the paraventricular nucleus of the ...
Oct. 6, 2025 — Researchers have enhanced vinegar’s antibacterial properties by infusing it with cobalt-based carbon nanoparticles. This nano-boosted solution kills harmful bacteria from both inside and outside their cells while remaining safe for humans. Tests ...
Oct. 6, 2025 — A major study from Tübingen found that prediabetic individuals who normalized their blood sugar through healthy habits — even without shedding pounds — cut their risk of type 2 diabetes by 71%. Researchers discovered that improved fat ...
Oct. 6, 2025 — A chance encounter with plastic waste on a tropical beach sparked a deep investigation into what those fragments mean for human health. The research reveals that bottled water isn’t as pure as it seems—each sip may contain invisible ...
Oct. 6, 2025 — A University of New Mexico scientist is revealing what might be one of the most overlooked causes of dementia — damage in the brain’s tiny blood vessels. Dr. Elaine Bearer has created a new way to classify these changes, showing that many people ...
Oct. 6, 2025 — Scientists studying tiny roundworms have uncovered how the secrets of a long life can be passed from parents to their offspring — without changing DNA. The discovery shows that when certain cellular structures called lysosomes change in ways that ...
Oct. 5, 2025 — Over 40% of fatal crash victims had THC levels far above legal limits, showing cannabis use before driving remains widespread. The rate didn’t drop after legalization, suggesting policy changes haven’t altered risky habits. Experts warn that the ...
Oct. 5, 2025 — A new study shows glioblastoma isn’t confined to the brain—it erodes the skull and hijacks the immune system within skull marrow. The cancer opens channels that let inflammatory cells enter the brain, fueling its deadly progression. Even drugs ...
Latest Headlines
updated 12:56 pm ET
Oct. 6, 2025 — In a remarkable blend of science and tradition, researchers have revived an old Balkan and Turkish yogurt-making technique that uses ants as natural fermenters. The ants’ bacteria, acids, and ...
Oct. 5, 2025 — Stanford scientists found that aging disrupts the brain’s internal navigation system in mice, mirroring spatial memory decline in humans. Older mice struggled to recall familiar locations, while a ...
Oct. 5, 2025 — Researchers from Leeds found that overeating is driven more by what people believe about food than by its actual ingredients or level of processing. Foods perceived as fatty, sweet, or highly ...
Oct. 5, 2025 — Scientists discovered that lifelong social support can slow biological aging. Using DNA-based “epigenetic clocks,” they found that people with richer, more sustained relationships showed younger ...
Oct. 5, 2025 — When cancer cells are physically squeezed, they mount an instant, high-energy defense by rushing mitochondria to the cell nucleus, unleashing a surge of ATP that fuels DNA repair and survival. This ...
Oct. 5, 2025 — Researchers have uncovered how a protein called MRAP2 acts as a key regulator of hunger. It helps move the appetite receptor MC4R to the cell’s surface, allowing it to send stronger “stop ...
Oct. 4, 2025 — A massive new study combining observational and genetic data overturns the long-held belief that light drinking protects the brain. Researchers found that dementia risk rises in direct proportion to ...
Oct. 4, 2025 — The STEP UP trials revealed that a 7.2 mg dose of semaglutide led to greater weight loss than the currently approved 2.4 mg dose. Nearly half of ...
Oct. 4, 2025 — Researchers uncovered a key cellular regulator, PP2A-B55alpha, that controls both the cleanup of damaged mitochondria and the creation of new ones. In Parkinson’s disease models, reducing this ...
Oct. 4, 2025 — Scientists discovered that vitamin D2 supplements can lower levels of vitamin D3, the form the body uses most effectively. Unlike D2, vitamin D3 enhances the immune system’s first line of defense ...