Naked Scientists Weekly: spinal cord breakthrough, embryo-editing ethics, Sicilian red fire ants, Bennu sample return, and tattoos vs sun exposure

Episode snapshot

The Naked Scientists episode surveys four major science stories and a public-ethics segment. It begins with a breakthrough in spinal cord repair using gene therapy to guide regrowing nerves through scar tissue in mice, followed by a discussion of the ethics of embryo editing and a citizen jury debate. The show then reports on alarming sightings of red fire ants in Sicily and why climate change could influence their spread, before detailing NASA’s Osiris-REx Bennu sample return and the scientific goals of studying asteroid material. A final segment answers a sun exposure question about whether tattoos can offer protection.

• Spinal cord injury breakthrough using beacon signals to direct nerve growth
• Civil discourse on embryo editing and the role of citizen juries in policy discussions
• Invasive red fire ants in Sicily and climate change implications
• Osiris-REx Bennu sample return and its scientific significance

Overview

The Naked Scientists convenes to discuss breakthroughs and debates in science, technology and medicine. The program opens with a report on a promising spinal cord regeneration approach and then pivots to discussions on the ethics of embryo editing and public engagement in science policy. The episode also covers ecological and planetary science stories, including invasive species in Europe and an upcoming asteroid sample return mission, before closing with a practical question about tattoos and sun exposure.

Spinal Cord Regeneration Breakthrough

Researchers in Switzerland demonstrated a method to guide regenerating nerve connections in the injured spinal cord. By delivering a beacon signal that acts like a homing cue, the team could direct growth through scar tissue and toward appropriate targets. This approach builds on developmental biology concepts and uses gene therapy to produce growth factors that create these beacons. In previous trials, regrowing nerves through the scar did not yield functional recovery, but the new signaling beacons allowed the regenerating wires to reach the correct destinations, enabling paralyzed mice to walk again over several weeks. The lead scientist explains that controlling guidance cues allows nerves to be steered rather than left to find their own way. The work was published in Science, illustrating a potential pathway toward restoring movement after spinal injuries, though the researchers emphasize it is early days and not a guaranteed cure.

Ethics of Embryo Editing and Citizens Jury

The program turns to the social and ethical dimensions of embryo editing. CRISPR-Cas9 technology has the potential to correct genetic diseases before birth, raising debates about consent, safety, and broader societal impact. A citizen’s jury assembled to scrutinize embryo editing discussions features participants who share lived experiences of rare conditions. The jury’s deliberations are portrayed as a mechanism to surface values and balance scientific possibility with public input. The discussion also revisits the 2018 He Jiankui case, which prompted global conversations about governance and public dialogue. The jurors eventually recommended that the UK government consider changes to the law to allow genome editing of human embryos to treat serious genetic conditions, while acknowledging that global consensus is unlikely and stressing the need for inclusive public conversation across patient communities and policymakers.

Invasive Red Fire Ants in Sicily

The episode reports 88 nests of the red fire ant Solenopsis invicta on the island of Syracuse in Sicily, highlighting the broader dangers of invasive species to biodiversity, ecosystems, and economies. Experts discuss how climate warming may facilitate the ants’ establishment in Southern Europe and what the main obstacles are to eradicating them. The conversation notes that eradication is challenging and often shifts to control strategies, drawing on New Zealand’s experience with invasive pests. The implications extend beyond ecology to agriculture and infrastructure, including potential damage to electrical systems and biodiversity losses. The scientists stress urgent mapping of the invaded area to inform local control measures before the ants spread further.

NASA Osiris-REx Bennu Sample Return

David Rothery explains the Osiris-REx mission which collected samples from the asteroid Bennu and is returning them to Earth. The capsule is expected to land in the Utah desert after a planned pass by Earth. Bennu’s composition is rich in carbon, making it scientifically valuable for understanding the early solar system and the building blocks of life. The analysis will compare Bennu samples to the Winchcombe meteorite, which was recovered after entering Earth’s atmosphere in 2021, to assess contamination and get a pristine laboratory examination. The mission’s broader goals include understanding potential planetary defense implications and what Bennu reveals about our origins.

Tattoo Sun Exposure Question

In a listener QOTW on whether tattoos protect skin from sunburn, dermatology experts explain that tattoo ink resides in the dermis, beneath the epidermal stem cells, so it cannot shield those stem cells from UV radiation. Melanin in the epidermis remains the primary protective factor, reducing UV damage to the deeper layers. Consequently, tattoos do not reduce skin cancer risk or UV-related damage to stem cells, though tattoos may contribute to skin aesthetics and screening awareness. The segment closes with thanks to participants and a tease for the next Titans of Science installment with Lord Robert Winston.