Scientists have discovered a virus with a slightly human trait that appears to contain a gene that was stolen from our ancestors about 100,000 years ago. This virus likely uses our human genes to infect us.
Viruses hijack genes
Previous studies have demonstrated that viruses are able to pick up genes from their host organisms. However, the new discovery - which was published last week in the journal Science - may represent the first known case of a virus carrying a human gene that it acquired at a relatively recent stage in evolutionary history. “This affects us more directly,” says Nils Ilde, an evolutionary biologist at the University of Utah who was not involved in this research.
The virus's prowess at stealing DNA
The way viruses reproduce makes them particularly adept at stealing DNA: they invade a cell, then take control of its vital mechanisms by injecting their own genes into it. The infected cell is then forced to produce copies of viral genes, as well as proteins that coat these genes, to create new viruses. Eventually, the new viruses burst out of the infected cell, leading to cell death.
Sometimes this process may be marred by errors, and part of the host's DNA is integrated into the new viral genes. This molecular error may pose a threat to human health.
A virus... a bacterial gene
For example, viruses that infect bacteria can pick up genes that the bacteria used to resist antibiotics. Although these genes do not directly benefit the viruses themselves, they allow them to transfer this DNA to other bacteria that they later infect. This is one way antibiotic resistance spreads.
A virus... with a human gene
Now scientists have discovered a virus that acquired a gene from humans. This gene was not hidden, or hard to find; It was discovered by Cedric Feschotte, a biologist at Cornell University, and his colleagues while examining databases of viral genes. “I can't believe no one has made this discovery before us,” Vichot says. “Anyone can find these genes literally within a few minutes.”
Vichot and his colleagues discovered the human gene within the molluscum contagiosum virus, a virus closely related to the smallpox virus. This virus causes small blisters to appear on the skin, which usually disappear spontaneously after a few months. This virus only infects humans, and often infects children.
The human gene in question, called PC200, is a mysterious gene. It produces a ribonucleic acid (RNA) molecule in the brain, the function of which scientists have not yet precisely determined. Some researchers believe that the PC200 gene contributes to controlling the rate of protein production within brain cells.
Invasion and takeover 100 thousand years ago
The PC200 gene found in the molluscum contagiosum virus contains mutations that are not found in the version carried by humans. These mutations have accumulated since the virus picked up the gene from our ancestors, allowing researcher Vichot and his colleagues to estimate that the virus took over this human gene about 100,000 years ago.
The RNA molecule encoded by the PC200 gene has a unique structure that may sometimes cause our cells to insert it into a new piece of deoxyribonucleic acid (DNA). This piece is later integrated into our genome, creating an additional copy of the BC200 gene.
178 copies of the gene “PC200” in the human genome
It seems that this process was repeated many times. Vichot and his colleagues detected 178 copies of the PC200 gene in the human genome, which have accumulated over millions of years. It is possible that this defect is the reason for the gene being transmitted to the virus as well. Whatever its method of arrival, the BC200 gene has been present in the virus for the past 100,000 years. Vichot did not find any sample of the “molluscum contagiosum” virus that did not contain the “PC200” gene, which indicates that the virus takes advantage of this human gene to its advantage.
Although the original function of the PC200 gene may have been related to regulating proteins in our brains, the virus appears to have found a new function for it. Researcher Ilde suggested that the “molluscum contagiosum” virus may use our genes to control the process of producing proteins, a process known as “conversion and transmission.” “Poxviruses love to manipulate the transformation and transmission process,” Ilde added.
Are there similar viruses that carry human genes?
Virus-infected cells sometimes try to shut down their protein factories to stop producing new viruses, but poxviruses are able to use host proteins to restart those factories. This may pose a problem for humans; Our PC200 gene likely provides this service to the molluscum contagiosum virus when we become infected.
Finally, Vichot wondered whether he and his colleagues had accidentally found an extremely rare example of a human gene inside a virus, or whether this phenomenon was common in viruses. “Honestly, this makes me want to do more research,” he said.
Millions of years old, “remnants of viruses” may reveal the secret of leukemia patients’ response to chemotherapy. A new study has shown that patterns of activity of these ancient viral sequences within the genome are associated with poor response to treatment. Their inclusion in AI models has enhanced the ability to predict which pathogens are most susceptible to treatment resistance.
The study was conducted by researchers from King's College London, who analyzed clinical and biological data for 271 patients with acute myeloid leukemia (AML), who received usual chemotherapy. The results were published in the journal Blood Neoplasia in August 2026, and indicated that what is known as the “dark genome” may contain additional indicators that will help in the future to improve treatment selection and develop more personalized strategies for leukemia patients.
When treatment doesn't work
Acute myelogenous leukemia begins in the bone marrow, can progress rapidly and interfere with the production of normal blood cells. Although a variety of tests are used to evaluate patients, doctors cannot yet accurately predict who will respond to chemotherapy and who will develop treatment-resistant disease.
In some cases, the patient does not achieve complete remission despite receiving treatment. The condition is known as treatment-resistant acute myelogenous leukemia, which makes choosing the appropriate treatment strategy a major challenge.
To investigate the possibility of improving prediction, the scientists developed three multi-layered machine learning models to which they gradually added different types of clinical and biological information. As for the final model, data related to the activity of ancient virus remnants found in the genome was added.
Viruses from the past inside our genes
These remnants are known as endogenous retroviruses (ERVs), and they are leftover parts of ancient viruses that infected human ancestors millions of years ago, then integrated into the genetic material and became part of the human genome.
These sequences are found mainly in non-coding parts of the genome, regions whose functions scientists still do not fully understand, and some of which are sometimes referred to as the “dark genome.”
These residues do not necessarily indicate the presence of an active viral infection, but their activity can affect a number of biological processes, including regulating the operation of genes and immune and inflammatory signals.
Artificial intelligence detects an additional signal
When the researchers added endogenous retroviral activity information to other clinical and molecular data, the model's ability to predict patients' response to chemotherapy improved.
The final model also recorded fewer false positives; That is, cases in which the model incorrectly predicts that a patient will develop treatment-resistant disease even though they are likely to respond to chemotherapy.
The researchers believe that these results indicate that information hidden in parts of the genome that often receive less attention may add value to traditional methods that focus on known genes.
Do the cells mimic a viral infection?
Scientists believe that one possible explanation is related to a phenomenon known as “viral mimicry,” where the cell behaves as if it is experiencing real viral activity. This may lead to the activation of immune and inflammatory signals within the cell; According to the hypothesis that the researchers are studying, these processes may help maintain some leukemia cells in a state that makes them more resistant to chemotherapy.
But the study does not yet prove that the activity of these viral sequences is the direct cause of treatment resistance, so this mechanism needs more research and experiments to confirm it.
Dr. Mohammad Mehdi Karimi, senior lecturer in bioinformatics at King's College London and lead author of the study, said that most cancer research focuses on traditional genes, while large parts of the “dark genome” remain less studied. He added that the results suggest the possibility of using a fingerprint derived from ancient viral sequences, along with traditional gene expression data, to help predict response to treatment.
A step towards more personalized treatment
The researchers stress that the results do not mean that the analysis of endogenous retroviruses has become a ready-made clinical test for making treatment decisions; Larger clinical studies are still needed to verify the model's accuracy and usefulness in different patient groups.
The researchers obtained patient data from the Beat AML trial, a landmark blood cancer precision medicine study launched in 2016.
The researchers believe that integrating “dark genome” signals with traditional clinical and genetic information may help in the future early identification of patients most susceptible to treatment resistance and support the development of more personalized treatment strategies for acute myelogenous leukemia.
It is widely accepted in neuroscience and medicine that the human brain is a single organ. However, recent research led by Stanford University School of Medicine shows results that contradict this long-held scientific belief; A new study published in the journal “Natural Neuroscience” indicates that the human brain originated from two separate organs, a discovery that may affect future treatment options for neurodegenerative diseases and brain disorders, according to the “Psychology Today” website.
The study was led by Kyle Loh, an associate professor at Stanford University, and conducted by authors Carolyn Dundes and Ryan Gokhai, along with a team of researchers from Stanford University, the University of California at San Francisco, and the California Institute of Technology in Pasadena, California.
The average person may find this reasonable, as it is known that the brain consists of two halves; Right brain and left brain. However, these are not the two areas that the researchers are referring to in this study. Instead, the two organs are a combination of the forebrain and midbrain working as a single unit, and the hindbrain.
In neuroanatomy, the brain consists of three main regions: the forebrain, the midbrain, and the hindbrain. The largest part of the adult human brain, the forebrain, is located in the front part of the brain and contains areas for higher cognitive functions such as reasoning, speech, management of voluntary movements, emotions, reproduction, eating, sleeping, and body temperature. The amygdala, hippocampus, hypothalamus, thalamus, and limbic system are all part of the forebrain.
The neocortex, located in the forebrain, is the youngest part of the brain and appears largely in mammals.
Connecting the large forebrain to the hindbrain is a much smaller area called the midbrain, which regulates vision, sensory processing, and motor reflexes. At the back of the head is the hindbrain, which regulates basic body functions such as the rhythm of breathing, sleep, movement, and heart rate.
The term “brainstem” refers to the part of the brain that connects it to the spinal cord, which is a combination of the midbrain and parts of the hindbrain, the pons, and the medulla oblongata.
Until recently the oldest part of the human brain was considered the reptilian part of the brain, which includes the brainstem and cerebellum. The concept of the “reptilian brain” was popularized thanks to the tripartite brain theory, which was presented in 1969 in a series of lectures given by Yale University physiologist and psychiatrist Paul MacLean (1913 - 2007). His theory divides the human brain along three distinct lines of development: the reptilian complex consisting of the brainstem, the ancient mammalian complex consisting of the limbic system, and the modern mammalian complex consisting of the neocortex.
However, the tripartite brain theory began to lose acceptance. A different study, published in the journal Science in 2022 by researchers from the Max Planck Institute for Brain Research, refutes the concept of the existence of an older brain region after discovering a group of similar neurons between mammals and lizards, located throughout the brain, despite a period of 320 million years of separate evolution.
How does the brain develop?
In this new study led by Stanford University, researchers sought to understand the process of brain evolution and determine the stage at which different brain regions differentiate. Specifically, they wanted to know whether the entire brain arises from a single ancestor or from several ancestors.
Progenitor cells are dividing cells that can reproduce and differentiate into different types of cells. Unlike stem cells, progenitor cells are pre-disposed to develop into a specific type of cell and can renew themselves a limited number of times. Stem cells can renew indefinitely and are able to differentiate into a variety of cells.
The team created a model using human pluripotent stem cells (hPSCs) along with laboratory mice. Pluripotent stem cells are undifferentiated adult stem cells that have been induced to resemble embryonic stem cells.
In 2006, Shinya Yamanaka discovered the method of induced pluripotent stem cells (iPSCs). These special cells have the ability to transform into any type of cell in the human body, as well as to renew themselves.
They discovered that during gastrulation (the stage of embryonic stomach formation), two brain progenitors arise at the same time and in parallel. Gastrulation is the stage during embryonic development that transforms the embryo from a single-layered, hollow ball of cells, called a blastocyst, into a multi-layered gastrula.
Researchers estimate that this process of parallel double evolution dates back to about 550 to 600 million years ago, and that it exists in many species such as primates, zebrafish, mice, chickens, and acorn worms.
This discovery may be a catalyst for an important shift in neuroscience, psychology, psychiatry and medicine. Furthermore, the ability to model functional hindbrain neurons may accelerate the development of new treatments for brain diseases and disorders in the future.
