In space, the body floats gently. So, if the conditions of gravity change, would the DNA packed inside cells also lose its arrangement?

A study offering a somewhat surprising answer to this question has been reported. A research team from New York University exposed human cells to simulated microgravity for 24 hours and found that the genome's arrangement and movement were largely maintained.

However, it's too early to conclude that "the human body is fine in space." The intrigue of this study lies not only in the resilience of cells but also in the difficulty of distinguishing the causes of changes observed in the experiment. The factor identified as damaging DNA was not the gravity conditions themselves but the flow of liquid inside the apparatus.

DNA is both a "string of characters" and a three-dimensional structure

When thinking of DNA, you might imagine a long string recording genetic information. However, inside cells, this long molecule is folded into a three-dimensional structure, forming chromatin along with proteins.

According to the original article, the cell nucleus, which houses about 2 meters of DNA, is only about 10 micrometers in size. Even just fitting a long thread into a small container seems challenging, yet cells must continue to use the necessary information within it.

Thus, to understand life, it's necessary to know not only what is written in the DNA but also how it is arranged and how it moves.

Associate Professor Alexandra Zidovska and her team at New York University focused on the relationship between this three-dimensional structure and the gravity that constantly acts on Earth. To discern the role of conditions that are always present, comparisons with altered conditions are necessary.

What does it mean to create "zero gravity" on Earth?

The research team designed a device called a Random Positioning Machine (RPM). It rotates a container with cells on two independent axes, continuously changing the direction of gravity relative to the cells.

A common misconception is that the device eliminates Earth's gravity. It is merely a terrestrial experimental method to simulate the effects of microgravity through rotation.

Moreover, gravity does not cease to exist when one goes into space. According to NASA, the weightlessness in orbit occurs because the spacecraft and the objects inside are in free fall together. The rotating device on Earth and the actual space environment cannot be treated as the same.

The aim of this experiment was not to replicate all conditions of space but to differentiate what happens to the cell nucleus and genome when stimuli related to gravity are altered.

The pitfall of the experiment is the "flow" inside the container

When the container is rotated, the liquid inside also moves. This means that in addition to changes in the direction of gravity, cells are subjected to forces from the flow of liquid.

If these two factors are mixed, it becomes difficult to determine whether changes in cell shape are due to gravity conditions or the stimulus from the flow.

To address this, the research team developed a rotation algorithm to minimize the flow of liquid. They also made efforts to eliminate bubbles that interfere with measurements and suppressed the problem of cell aggregation.

They compared conditions of simulated microgravity with minimized flow, conditions exposed to strong flow, and control conditions without these treatments.

This is a step beyond experiments that merely compare rotated cells with stationary cells. It aimed not only to find that something changed but also to verify "what caused the change."

The nucleus changed. Yet the genome remained stable

After 24 hours of treatment, the research team used image analysis to examine the shape and volume of cells and nuclei, the nuclear membrane, and the arrangement and movement of the genome.

The results were not uniformly "no change."

In simulated microgravity, the volume of the cell nucleus increased, while the overall shape of the cell was largely maintained. There were no significant changes observed in the thickness or structure of the nuclear membrane.

Notably, the arrangement and movement of the genome were preserved, and no DNA damage due to simulated microgravity was observed under the experimental conditions.

In contrast, cells exposed to flow became elongated, and DNA damage was observed. The surface of nucleoli inside the nucleus became smoother under both simulated microgravity and flow conditions.

Even if there are changes to the "container" of the cell nucleus, it doesn't necessarily mean the genome inside will be significantly disrupted immediately. The results indicate that, at least within a 24-hour period, the physical structure and movement of the genome remain stable.

Don't equate this to "DNA is unharmed in space"

This finding carries conditional hope. However, those conditions must not be overlooked.

First, the observation period is 24 hours. It's unknown whether the same results would occur if it continued for weeks or months. Researchers also mention the possibility that small changes could amplify over time, affecting cellular functions.

Next, experiments with cultured cells do not equate to humans living in space. This experiment alone cannot evaluate all potential causes of DNA damage that might occur during space habitation.

Furthermore, the result that the genome's arrangement and movement were maintained does not mean that the function of all genes and cellular functions remain unchanged. It's necessary to distinguish between the indicators examined and the scope of conclusions that can be drawn from them.

To be precise, the discovery is that "under the conditions and measurement range of this experiment, the genome's arrangement and movement did not significantly deteriorate after 24 hours of simulated microgravity."

What was the reaction on social media? The emphasis on conditions in official announcements

On social media, Phys.org introduced this research on its official LinkedIn account. The post conveyed that the genome's arrangement and movement were maintained under 24 hours of simulated microgravity, the volume of the cell nucleus increased, and the effects of long-term exposure remain unknown.

However, as of September 24, 2026, the range of publicly available information confirmed did not allow for sufficient collection and verification of comments from general users. Therefore, it is not possible to indicate trends in public opinion such as "voices of reassurance are widespread on social media" or "expectations for space migration are rising." Official introduction posts should be distinguished from general user reactions.

With that in mind, the points of discussion when reading this research are clear. What happens beyond 24 hours? To what extent do the results of simulated experiments on Earth match those in actual space? And how much can the flow created by the experimental apparatus be suppressed? These are future questions derived from the research results, not from confirmed social media comments.

Advancing space research requires technology to "separate causes"

This study cannot be read as a safety declaration for space travel. Nonetheless, it provides an important clue for understanding what happens to life in space.

Even if changes occur in cells, misidentifying the cause could lead to incorrect countermeasures. The method of separately examining simulated microgravity and liquid flow will likely help in more cautiously interpreting future experimental results.

Moreover, it is intriguing that even when the usual condition of gravity is altered, the genome's arrangement and movement did not immediately collapse. Not all parts of a cell react the same way to environmental changes.

What will happen to the blueprint of humans in space? The answer is still in progress. The 24 hours demonstrated short-term stability and the necessity to confirm it over a longer period.

Sources

1. Provided by Phys.org/New York University "Uncovering gravity's impact on the human genome" (September 23, 2026). Organized experimental methods, observations after 24 hours, and explanations from researchers.
   https://phys.org/news/2026-09-uncovering-gravity-impact-human-genome.html

2. Published in Science Advances "The Effect of Microgravity and Flows on the Organization and Dynamics of the Human Genome." DOI of the research paper.
   https://www.science.org/doi/10.1126/sciadv.aeh3116

3. List of papers from the Zidovska Lab at New York University. Confirmed the title, authors, and journal of the relevant paper. Listed as In Press at the time of confirmation.
   https://physics.nyu.edu/zidovskalab/pubs.html

4. NASA "What is Microgravity?" Primary source explaining the relationship between microgravity and free fall. Used as a supplement to avoid the misconception that "there is no gravity in space."
   https://www.nasa.gov/centers-and-facilities/glenn/what-is-microgravity/

5. Official LinkedIn post by Phys.org. Social media announcement conveying the stability of the genome over 24 hours and the unknown long-term effects. Not a source indicating reactions from general users.
   https://www.linkedin.com/posts/phys-org_uncovering-gravitys-impact-on-the-human-activity-7508586672343683072-BLu_