Spanish National Research Council (CSIC)

A team from the Netherlands has successfully edited pathogenic mutations in mitochondrial DNA in human cells, changes in DNA that cause disease, according to research published in PLoS Biology. The authors used a genetic tool known as a base editor. Until now, techniques derived from CRISPR have made it possible to correct mutations in nuclear DNA, and new techniques are being developed that allow mitochondrial DNA to be edited.

A team from Stanford University (USA) has analysed the conservation status of 1,376 species of scavenger animals. The results, published in the journal PNAS, indicate that 36% of them are threatened or in decline, especially large species and obligate scavengers, which depend exclusively on carrion for food. In contrast, the number of small and facultative scavengers, such as rodents, for which carrion is not their only source of food, is increasing. According to the authors, this ‘could increase the risks of diseases that large scavengers have helped to mitigate’.

Over the last seven decades, the frequency of planetary wave resonance phenomena has tripled, according to a study published in PNAS. The authors argue that the risk of extreme weather events related to this phenomenon during the northern hemisphere summer could be higher than current model estimates.

A model has analysed mercury concentrations in rivers around the world from 1850 to the present day. The results, published in Science Advances, conclude that levels have doubled and even tripled since the Industrial Revolution: before 1850, rivers carried approximately 390 metric tonnes of mercury to the oceans each year, and today that figure has risen to around 1,000 metric tonnes. According to the authors, these results have implications for human health and wildlife, as mercury compounds are neurotoxic, can accumulate in fish and pose a health risk through consumption.

An international research project involving Spanish participation has analysed the distribution of brown bears in Europe and Turkey. To do this, the team studied more than three million locations belonging to some 3,000 bears, with data from 14 European and Turkish subpopulations in very different environments. The main conclusion is that bears occupy areas where the species that form part of their diet are distributed. The study, published in Global Change Biology, shows that the influence of climate change on these species also has an impact on the distribution of bears.

A team from China has analysed the genetic data of more than 450,000 people and identified a variant in a gene that contributed to increased height and basal metabolic rate in modern humans, especially when meat consumption increases. In addition to providing insight into evolutionary processes, the finding ‘also has important implications for understanding susceptibility and resistance to contemporary metabolic disorders such as type 2 diabetes, obesity and metabolic syndrome,’ according to the authors. The results are published in the journal Cell Genomics.

A US study analysing data from nearly 700,000 people concluded that those with a history of herpes simplex virus (HSV-1) infections were at greater risk of developing Alzheimer's disease. The study, published in BMJ Open, also showed that patients with this virus who used anti-herpes treatments were less likely to develop the disease.

New gene editing technologies, such as gene drive tools, open the door to deliberately extinguishing species. An analysis article published in Science examines the ethical implications of this possibility based on three specific examples: the eradication of rats, the cattle barren worm, and the Anopheles gambiae mosquito, which transmits malaria. The analysis attempts to answer the question: ‘When and under what circumstances could the intentional eradication of a species be justified?".

A team from the Children's Hospital of Philadelphia and Penn Medicine (United States) has successfully treated a baby diagnosed with a rare genetic disorder using personalised CRISPR gene editing therapy. The baby, known only by the initials KJ, was born with a rare metabolic disease known as severe carbamoyl phosphate synthetase 1 (CPS1) deficiency. After spending the first months of his life in hospital on a very restrictive diet, KJ received the first dose of his tailored therapy in February 2025, between six and seven months of age. The treatment, which is being used for the first time for this type of disorder, was administered safely, and the baby is now growing well and improving. The case is detailed in a study published by The New England Journal of Medicine (NEJM).

A team from the Centre for Genomic Regulation (CRG) and Pompeu Fabra University (UPF) in Barcelona has developed an artificial intelligence tool capable of designing regulatory sequences for genes that do not exist in nature. When introduced into cells, these enhancers can increase or decrease gene activity in a specific way depending on the type of cell targeted. According to the authors, ‘the potential applications are enormous. It's like writing software, but for biology.’ The results are published in the journal Cell.