Tijeras para el ADN: la promesa y el dilema de CRISPR

Enfermedades como la fibrosis quística, la anemia falciforme, o la enfermedad de Huntington.

Diseases like cystic fibrosis, sickle cell anemia, or Huntington's disease.

CRISPR ofrece la posibilidad de corregir ese error directamente en el genoma.

CRISPR offers the possibility of correcting that error directly in the genome.

The sickle cell story is particularly striking to me.

In late 2023, the FDA approved the first CRISPR-based therapy for sickle cell disease.

A disease that has caused immense suffering, particularly in African and African American communities, for generations.

And now there's a treatment.

La verdad es que ese es un avance extraordinario.

The truth is that is an extraordinary advance.

Hay pacientes que han recibido este tratamiento y que ya no sufren los dolores devastadores que tenían antes.

There are patients who have received this treatment and no longer suffer the devastating pain they had before.

Y también hay investigaciones muy avanzadas sobre ciertos tipos de cáncer, donde CRISPR se usa para modificar las células del sistema inmunitario del propio paciente para que ataquen al tumor.

And there is also very advanced research into certain types of cancer, where CRISPR is used to modify the cells of the patient's own immune system to attack the tumor.

I mean, this sounds almost unambiguously good so far.

Curing disease, ending inherited suffering.

So where does it tip into genuinely difficult ethical territory?

Because it clearly does.

Mira, el momento en que todo se complicó fue en noviembre de 2018.

Look, the moment everything got complicated was in November 2018.

Un científico chino llamado He Jiankui anunció que había creado los primeros bebés humanos con su genoma editado.

A Chinese scientist named He Jiankui announced that he had created the first human babies with their genome edited.

Dos gemelas.

Two twin girls.

Y lo anunció en un congreso científico internacional, como si esperara aplausos.

And he announced it at an international scientific conference, as if he expected applause.

He did not receive applause.

The extraordinary thing is how fast the scientific community turned on him.

Within days, researchers around the world were calling it reckless, irresponsible, a profound ethical violation.

What exactly had he done?

He Jiankui editó el genoma de dos embriones humanos antes de implantarlos en el útero de su madre.

He Jiankui edited the genome of two human embryos before implanting them in their mother's uterus.

Modificó un gen llamado CCR5, que es el gen que el virus del VIH usa para entrar en las células.

He modified a gene called CCR5, which is the gene the HIV virus uses to enter cells.

Su argumento era que quería proteger a las niñas del VIH porque su padre era seropositivo.

His argument was that he wanted to protect the girls from HIV because their father was HIV-positive.

Right, so on the surface, you could construct a sympathetic narrative.

Father has HIV, scientist wants to protect the children.

But the problem runs much deeper than the stated motivation.

What's the actual line that was crossed here?

Es que hay una distinción fundamental que él ignoró completamente.

The thing is, there's a fundamental distinction that he completely ignored.

Existe una diferencia enorme entre editar las células de una persona que ya vive, lo que se llama edición somática, y editar un embrión antes de nacer.

There is an enormous difference between editing the cells of a person who is already alive, which is called somatic editing, and editing an embryo before birth.

Cuando editas un embrión, esos cambios se transmitirán a todos sus descendientes para siempre.

When you edit an embryo, those changes will be passed on to all of its descendants forever.

So the line is the germline, literally.

Changes to somatic cells, body cells, affect only that patient.

But germline editing, changes to an embryo, ripple forward through every future generation of that family's descendants.

That's why it's categorically different.

Exactamente.

Exactly.

Y además, hay otro problema serio.

And there's another serious problem as well.

Esas niñas no pudieron dar su consentimiento.

Those girls could not give their consent.

Ningún ser humano puede consentir cambios permanentes en su propio genoma antes de nacer.

No human being can consent to permanent changes in their own genome before they're born.

Es una decisión que alguien tomó por ellas, por sus hijos, por sus nietos, sin ningún tipo de consulta posible.

It's a decision someone made for them, for their children, for their grandchildren, without any possible consultation.

The consent issue is enormous and it gets more uncomfortable the longer you sit with it.

Because the moment you say germline editing is acceptable under some circumstances, you open a door.

And behind that door is the question that nobody in this field wants to answer directly.

La pregunta de los bebés de diseño.

The question of designer babies.

Si es aceptable editar un gen para eliminar una enfermedad, ¿por qué no editar genes para elegir la inteligencia, la altura, el color de los ojos?

If it's acceptable to edit a gene to eliminate a disease, why not edit genes to choose intelligence, height, eye color?

La tecnología no distingue entre curar una enfermedad y mejorar características que simplemente se consideran deseables.

The technology doesn't distinguish between curing a disease and enhancing characteristics that are simply considered desirable.

And here's where the historical weight of this question becomes almost unbearable.

Because humanity has been down a version of this road before, and it ended catastrophically.

The word that nobody wants to say but that everyone is thinking is eugenics.

La eugenesia.

Eugenics.

Sí.

Yes.

Y es importante decirlo sin miedo.

And it's important to say it without fear.

En el siglo XX, la idea de mejorar la raza humana seleccionando características genéticas llevó a esterilizaciones forzadas en Estados Unidos, en Suecia, en muchos países.

In the 20th century, the idea of improving the human race by selecting genetic characteristics led to forced sterilizations in the United States, in Sweden, in many countries.

Y en su forma más extrema, llevó al Holocausto.

And in its most extreme form, it led to the Holocaust.

No es una comparación exagerada, es la historia real.

It's not an exaggerated comparison, it's actual history.

I spent time in Germany years ago covering a story, and the sensitivity around anything that touches genetic selection is palpable in a way that's different from almost anywhere else I've been.

Europe carries this history in its bones.

Bueno, en Europa tenemos razones muy concretas para ser cautelosos.

Well, in Europe we have very concrete reasons to be cautious.

Pero también creo que hay una diferencia importante entre lo que hicieron los regímenes totalitarios, que imponían sus decisiones sobre toda la población, y una tecnología que podría, en teoría, estar en manos de padres individuales que toman decisiones sobre sus propios hijos.

But I also think there's an important difference between what totalitarian regimes did, which imposed their decisions on the entire population, and a technology that could, in theory, be in the hands of individual parents making decisions about their own children.

I hear that distinction, but I want to push back on it a little.

Because the individual choice argument leads directly to another problem, and it might be the sharpest one.

If this technology is available, who is actually going to have access to it?

Eso es el argumento de la desigualdad, y es muy poderoso.

That's the inequality argument, and it's very powerful.

Hoy, el tratamiento de CRISPR aprobado para la anemia falciforme cuesta aproximadamente dos millones de dólares por paciente.

Today, the approved CRISPR treatment for sickle cell anemia costs approximately two million dollars per patient.

Dos millones.

Two million.

Si la edición genética se convierte en una opción para mejorar características, solo los ricos podrán acceder a ella.

If genetic editing becomes an option to enhance characteristics, only the wealthy will be able to access it.

So you end up with a world where the wealthy can literally purchase biological advantages for their children that are then heritable.

Permanently.

You've just encoded economic inequality into the genome of the species.

That's not a slippery slope argument, that's a straight line.

La verdad es que es un escenario que muchos científicos y filósofos describen como la creación de dos especies humanas distintas.

The truth is it's a scenario that many scientists and philosophers describe as the creation of two distinct human species.

No de forma inmediata, sino en generaciones.

Not immediately, but over generations.

Una clase que ha sido mejorada genéticamente y otra que no ha tenido acceso a esa mejora.

A class that has been genetically enhanced and another that has had no access to that enhancement.

Es una posibilidad que obliga a tomarse en serio la regulación.

It's a possibility that demands serious regulation.

Let's shift for a moment, because CRISPR isn't only about human medicine.

There's a whole other dimension here, which is agriculture.

And I think the public tends to lump CRISPR-edited crops together with traditional GMOs, which may not be entirely fair.

A ver, hay una diferencia técnica importante.

Well, there's an important technical difference.

Los transgénicos tradicionales introducen genes de una especie en otra, lo cual es algo que no ocurriría de forma natural.

Traditional GMOs introduce genes from one species into another, which is something that would not occur naturally.

CRISPR, en cambio, puede hacer cambios dentro del genoma de la propia planta, sin añadir material genético externo.

CRISPR, on the other hand, can make changes within the plant's own genome, without adding external genetic material.

Pero entiendo que para mucha gente esa distinción es difícil de apreciar.

But I understand that for many people that distinction is hard to appreciate.

The thing is, the GMO debate poisoned the well pretty thoroughly, especially in Europe.

And I wonder how much of the resistance to CRISPR in agricultural contexts is a hangover from that fight, rather than a response to the actual science of what CRISPR is doing.

Es que hay un problema de confianza que va más allá de la ciencia.

The thing is there's a trust problem that goes beyond the science.

La Unión Europea durante años reguló las plantas editadas con CRISPR igual que los transgénicos, lo cual muchos científicos consideraban exagerado.

The European Union for years regulated CRISPR-edited plants the same as GMOs, which many scientists considered excessive.

Recientemente han empezado a cambiar esa posición, pero el desconfianza del público no desaparece solo porque cambie una regulación.

Recently they've started to change that position, but public mistrust doesn't disappear just because a regulation changes.

And trust is really the underlying currency in all of this, isn't it.

Trust in scientists, trust in regulators, trust in pharmaceutical companies, trust in governments to make decisions that are actually in the public interest rather than corporate interest.

Mira, el caso de He Jiankui fue un desastre para esa confianza.

Look, the He Jiankui case was a disaster for that trust.

Aquí estaba un científico que había recibido formación en las mejores universidades del mundo, que entendía perfectamente por qué había líneas que no se deben cruzar, y las cruzó de todas formas.

Here was a scientist who had been trained at the best universities in the world, who understood perfectly well why there are lines that should not be crossed, and he crossed them anyway.

Fue a la cárcel tres años, pero el daño a la confianza pública fue mucho más duradero que su condena.

He went to prison for three years, but the damage to public trust lasted much longer than his sentence.

So the question becomes, who actually has the authority to set the rules?

Right now, this is fragmented by country.

What happens in China isn't governed by American regulations, and what happens in some biotech hub isn't necessarily governed by either.

Is there any real international governance here?

Bueno, hay organismos internacionales que han intentado crear marcos de referencia.

Well, there are international organizations that have tried to create reference frameworks.

La OMS publicó recomendaciones.

The WHO published recommendations.

Hay comités científicos que piden una moratoria global sobre la edición de la línea germinal humana.

There are scientific committees calling for a global moratorium on human germline editing.

Pero la realidad es que no existe ningún tratado vinculante que prohíba esto a nivel mundial.

But the reality is that there's no binding treaty that prohibits this globally.

Cualquier país puede hacer lo que quiera dentro de sus fronteras.

Any country can do what it wants within its borders.

Which means, in practice, that you have a race dynamic.

If one country decides to push forward with enhancements, others face pressure to follow or fall behind.

It's a logic that's deeply familiar from other technologies, from nuclear weapons to artificial intelligence.

The collective action problem is always the hardest part.

La verdad es que es el dilema clásico de la tecnología transformadora.

The truth is it's the classic dilemma of transformative technology.

La ciencia avanza más rápido que nuestra capacidad de crear normas éticas y jurídicas para controlarla.

Science advances faster than our capacity to create the ethical and legal norms to govern it.

No es que los científicos sean irresponsables, es que las instituciones humanas son lentas y la tecnología no espera.

It's not that scientists are irresponsible, it's that human institutions are slow and technology doesn't wait.

I want to come back to something Octavio said early on, about this being both fascinating and terrifying.

Because I think what makes this particular technology different from, say, the nuclear bomb, is that CRISPR's most immediate applications genuinely could end enormous amounts of human suffering.

That's not propaganda.

That's real.

No, no, espera, estoy completamente de acuerdo en eso.

No, no, wait, I completely agree on that.

Cuando pienso en una familia que lleva generaciones conviviendo con una enfermedad hereditaria devastadora, y que de repente existe la posibilidad de que eso termine, eso es profundamente humano y profundamente bueno.

When I think about a family that has lived with a devastating hereditary disease for generations, and that suddenly there's the possibility of it ending, that is profoundly human and profoundly good.

El problema no es la tecnología en sí misma.

The problem isn't the technology itself.

El problema es cómo decidimos usarla colectivamente.

The problem is how we decide to use it collectively.

And that's maybe the most honest place to end up.

Not with a verdict, but with a genuine acknowledgment that the conversation itself is the work.

The scientific community, philosophers, ethicists, patients, lawmakers, all of them have to be in the room together.

Not separately.

Exacto.

Exactly.

Y creo que lo más valioso que podemos hacer es entender bien de qué estamos hablando antes de tener esa conversación.

And I think the most valuable thing we can do is understand clearly what we're talking about before having that conversation.

CRISPR no es magia, no es ciencia ficción, no es una amenaza abstracta.

CRISPR is not magic, not science fiction, not an abstract threat.

Es una herramienta real que ya existe, que ya se usa, y que ya ha cambiado vidas.

It's a real tool that already exists, that is already being used, and that has already changed lives.

La pregunta es qué vidas va a cambiar en el futuro, y quién va a decidir eso.

The question is which lives it will change in the future, and who is going to decide that.