Ethics, Private Interests and the Public Good
In February 2025, a medical team at Children's Hospital of Philadelphia administered a revolutionary treatment to six-month-old KJ, who was born with a rare genetic disorder that prevented his body from processing ammonia . Typically fatal in the first week of life, CPS1 deficiency had kept KJ hospitalized since birth, surviving on a severely restricted diet and multiple medications .
Within six months of his diagnosis, scientists had designed a personalized CRISPR treatment that corrected the exact genetic error causing his condition. After three doses, KJ was not only surviving but thriving—able to tolerate normal childhood illnesses and increased dietary protein without dangerous ammonia spikes 3 .
This medical miracle represents both the extraordinary promise of gene editing technology and the complex ethical questions it raises. As Dr. Kiran Musunuru, one of the lead researchers on KJ's case, reflected: "The promise of gene therapy that we've heard about for decades is coming to fruition, and it's going to utterly transform the way we approach medicine" .
Yet beneath this triumph lies an uncomfortable reality: who will have access to these lifesaving treatments that can cost millions to develop? As private companies race to commercialize gene editing, tensions between profit motives and the public good are creating new ethical battlegrounds that will shape the future of human genetic modification.
CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) originated as a natural defense system in bacteria, which use it to recognize and cut the DNA of invading viruses 7 . Scientists have repurposed this system into a powerful gene-editing tool that works like molecular scissors, capable of snipping DNA at precise locations in a genome 6 .
The most common system, CRISPR-Cas9, consists of two key components: the Cas9 enzyme that cuts DNA and a guide RNA molecule that directs Cas9 to the exact sequence scientists want to modify 7 .
Molecular scissors that precisely cut DNA at targeted locations
Targets specific DNA sequences with unprecedented accuracy
Dramatically faster than previous gene-editing technologies
Significantly cheaper than earlier methods like ZFNs and TALENs
Recent advances have moved beyond simple DNA cutting to even more precise techniques:
Developed in David Liu's lab nearly a decade ago, allows scientists to change single DNA letters without breaking the DNA backbone 3 . This approach was used successfully in KJ's treatment to correct his specific mutation .
These technologies have expanded CRISPR's therapeutic potential, enabling researchers to target thousands of genetic mutations behind conditions like sickle cell disease, progeria, and Tay-Sachs 3 .
The treatment of baby KJ represents a landmark in personalized gene therapy, demonstrating that customized CRISPR treatments can be developed rapidly for individual patients with rare genetic conditions .
KJ's specific CPS1 mutation was identified soon after his birth .
Researchers designed a base editing therapy that would correct KJ's exact genetic error .
The treatment was delivered via lipid nanoparticles (LNPs) that naturally accumulate in the liver, the organ affected by CPS1 deficiency 5 .
Unlike earlier CRISPR treatments delivered via viral vectors, the LNP delivery system allowed doctors to safely administer multiple doses—KJ received three infusions over several months 5 .
The collaborative effort brought together researchers from:
This unprecedented collaboration enabled the team to compress what would normally be "many years" of development into "less than seven months" 3 .
The results, published in The New England Journal of Medicine, demonstrated both the safety and efficacy of this approach . KJ showed significant clinical improvement, including:
As of April 2025, KJ continued to grow well and was preparing to go home to his family—a outcome nearly unthinkable for infants with severe CPS1 deficiency just months earlier .
| Time Period | Key Developments | Significance |
|---|---|---|
| Before August 2024 | KJ born with CPS1 deficiency | Typically fatal in first week of life |
| August 2024 | Specific genetic variant identified | Enabled design of personalized therapy |
| February 2025 | First dose of bespoke base editing therapy | First-ever personalized in vivo CRISPR treatment |
| March-April 2025 | Second and third doses administered | Demonstrated safety of multiple LNP deliveries |
| April 2025 | KJ thriving, tolerating protein, needing less medication | Proof of concept for individualized gene therapy |
| Research Reagent | Function | Example from KJ's Case |
|---|---|---|
| CRISPR-Cas9 System | Creates targeted double-strand breaks in DNA | Not used—base editing preferred for precision |
| Base Editors | Chemically converts one DNA base to another without double-strand breaks | Corrected KJ's specific point mutation 3 |
| Prime Editors | Searches for and replaces specific DNA sequences | Used in separate CGD trial for precise insertion 3 |
| Lipid Nanoparticles (LNPs) | Delivery vehicles that protect and transport editing components | Delivered base editors to KJ's liver 5 |
| Viral Vectors | Modified viruses that deliver genetic material | Not used—avoided immune response risks 5 |
| Guide RNA (gRNA) | Molecular address that directs editors to target DNA sequence | Specified the exact location of KJ's mutation 7 |
The choice of lipid nanoparticles over viral vectors in KJ's case proved particularly significant. As noted in clinical updates, "LNPs don't trigger the immune system like viruses do, opening up the possibility for redosing" 5 . This allowed doctors to administer additional doses to increase the percentage of edited cells—a crucial advantage over viral delivery methods.
The staggering cost of gene therapies represents one of the most pressing ethical challenges. Current CRISPR-based medicines can cost "upwards of $2 million per patient" and are "often denied coverage by public health bodies and private insurance, limiting their access to the most wealthy" 2 .
This creates what some ethicists fear could become a "genetic underclass" 7 , where wealthier individuals can access enhancements or treatments unavailable to others.
Henry Greely's warning in "CRISPR People" paints a concerning picture: "affluent families may use CRISPR to engineer their children with specific traits relating to enhanced intelligence or athletic capability" 7 . This could lead to a society where genetic privilege creates generational disparities that become permanently embedded in human biology 7 .
The 2018 case of Chinese biophysicist He Jiankui, who created the world's first gene-edited babies, shocked the scientific community and highlighted the need for clear ethical boundaries 6 7 . Though He was sentenced to three years in prison for violating medical regulations, his return in 2025 with a new venture aimed at editing human embryos for disease resistance has renewed ethical concerns 6 .
The tension between therapeutic applications and enhancement raises difficult questions:
Between preventing disease and pursuing enhancement? 2
Could the technology reinvigorate social Darwinism by suggesting that people are poor because of genetic inferiority rather than social injustice? 6
Might we see the emergence of commercial enterprises offering genetic selection for non-disease traits like height or IQ? 6
As Monash University philosophy professor Robert Sparrow warns, gene editing could reinforce elitism, resulting in "a two-tiered society where the rich can buy genetic advantages" 6 .
Beyond human medicine, gene editing promises significant benefits for agriculture and environmental sustainability. Researchers argue that New Genomic Techniques (NGTs) could help achieve European Green Deal goals by developing crops that are "climate resilient, produce higher yields, and require less fertilizers and pesticides" 8 .
Yet the European Commission's proposal to allow NGTs in conventional but not organic farming creates what researchers call a "formidable hurdle" for identification, labeling, and traceability 8 . The debate highlights broader concerns about "naturalness" and whether gene editing represents an appropriate human intervention in natural systems 2 .
The treatment of baby KJ represents both the extraordinary potential of gene editing and the challenges that lie ahead. As Dr. Rebecca Ahrens-Nicklas, who led KJ's treatment team, reflected: "Years and years of progress in gene editing and collaboration between researchers and clinicians made this moment possible, and while KJ is just one patient, we hope he is the first of many to benefit" .
The path forward requires balanced regulation that neither stifles innovation nor allows commercial interests to override ethical considerations.
This includes ensuring that marginalized communities and developing nations have a voice in how these technologies are developed and deployed 7 .
David Liu, whose lab developed both base editing and prime editing, emphasizes the societal importance of supporting basic science: "It's easy to forget that every translation of science into a societal benefit began as a basic science project" 3 .
As we stand at the threshold of being able to rewrite our genetic code, we face not only scientific and medical challenges, but fundamental questions about what kind of society we want to create—one where genetic advantages are available only to those who can afford them, or one where the benefits of this revolutionary technology are accessible to all.