Pompeu Fabra University

In 2025, a six-year-old Chinese girl named Mei (not her real name) became the first person in the world to undergo gene-editing therapy targeting the brain. She had a developmental delay associated with a rare genetic syndrome, Snijders-Blok-Campeau syndrome. According to Science, her parents had raised $860,000 to partially fund the treatment at Xinhua Hospital in Shanghai (China), led by Zilong Qiu, one of the neuroscientists competing to apply base editors — a version of CRISPR — in children with rare diseases. Now, Science and Retraction Watch have exclusively revealed that Mei died from a severe immune reaction seven days after receiving the treatment, a story that had been kept hidden. The entry on clinicaltrials.gov has not been updated since 2025; and when Qiu and his team published animal studies related to the trial in the journal Nature in early 2026, according to the journalistic investigation, they omitted any reference to Mei and her family.

The range of CRISPR tools for genome editing can extend beyond nature-inspired designs thanks to proteins designed using artificial intelligence. A new study by Nobel laureate Jennifer Doudna’s team, published in Science, describes the design of synthetic RNA-guided nucleases, with sequences substantially different from those found in nature, which match or exceed the activity of their natural counterparts whilst offering novel properties.

In December 2025, the European Commission proposed new rules for the placing on the market of genetically modified microorganisms (GMMs). Tomorrow, European Union health ministers will vote to adopt the position of the Council of the European Union (EU) on this proposal. The Commission, the Council, and the European Parliament must agree on the final version of the legislative text.

The origin and the process by which eukaryotic cells arose remains one of the great unanswered questions in biology, with Lynn Margulis’s theories regarding the incorporation of a bacterium that would later become the mitochondrion marking a major turning point. Now, Spanish research carried out by IRB Barcelona and the Barcelona Supercomputing Center challenges this view. Without denying the role of mitochondria, it suggests that the process was longer and more complex than previously thought, stretching over hundreds of thousands of years. At least two other different bacteria contributed to the development of eukaryotic cells, and giant viruses appear to have acted as vehicles for genetic transfer. The findings, published in Nature, suggest a much more protracted and gradual process of exchange between microorganisms.

Formaldehyde is a preservative used on human tissue; inhaling it has harmful health effects and it is considered a human carcinogen. A study published in Occupational & Environmental Medicine shows that airborne concentrations of this compound in most pathological anatomy departments of the UK’s National Health Service (NHS) are rarely monitored and regularly exceed the occupational exposure limits set by the European Union (EU): seven out of 10 departments exceeded the eight-hour maximum exposure limit set by the EU.

An international team led by the Institute of Evolutionary Biology (IBE), a joint center of the Spanish National Research Council (CSIC) and Pompeu Fabra University (UPF), has compiled the largest genetic database of Native American populations to date, including 128 new complete genomes. The research identified more than one million genetic variants not previously observed in other populations, revealing a unique genetic diversity. According to the authors, who published their work in Nature, “these results demonstrate the need to better represent these populations in genomics.”

Premature births, babies born with birth defects, bad luck, satellite and telecommunications failures… Eclipses are attributed with a wide variety of consequences that have no scientific basis and are largely rooted in cultural traditions and deep-seated misconceptions. With the help of expert sources, in this article we explain why some people believe in them, what the main risks are and how to counter them. 

In the ephemeral pools along the coasts of the Caribbean island of Curaçao lives Choanoeca flexa, a tiny unicellular aquatic organism belonging to the choanoflagellates, important for being close relatives of animals. As the pools evaporate and refill, C. flexa can switch between unicellular and multicellular forms in three different ways: by division, by aggregation, or by combining both, mechanisms that were previously thought to be mutually exclusive. The discovery, published today in Nature, may challenge current understanding of the origins of multicellular life.

A study published in the European Heart Journal shows that people with type 1 and type 2 diabetes have a higher risk of sudden cardiac death than those without these diseases. In addition, their life expectancy is lower. The research analysed data from 6,862 cases of sudden cardiac death in Denmark in 2010, and concluded that the incidence of these deaths is 3.7 times higher in people with type 1 diabetes than in the general population, and 6.5 times higher in people with type 2 diabetes. Those under the age of 50 were at the highest risk.

Gilberto and Tomás are two macaques trained to synchronise their movements with the rhythm of a metronome, who were also able to tap to a musical beat, according to a study published in Science. This result contradicts the vocal learning hypothesis, according to which only species capable of complex vocalisations can perceive and follow a musical rhythm.