# Most diseases need treatment tailored to individual biology

Markdown copy of https://realalpha.app/s/most-diseases-need-treatment-tailored-to-individual-biology/ on Real Alpha, the best minutes from long interviews with the people building AI. Cite and link the page, not this copy.

- Speaker: [Priscilla Chan](https://realalpha.app/people/priscilla-chan/) · Chan Zuckerberg Initiative
- Host: [Erik Torenberg](https://realalpha.app/people/erik-torenberg/) · General partner, Andreessen Horowitz · Helped build Product Hunt; founded On Deck, Village Global and Turpentine.
- Show: a16z Podcast
- Episode: [Mark Zuckerberg & Priscilla Chan: How AI Will Cure All Disease](https://realalpha.app/v/YnV8pgHtO5Y/), Nov 6, 2025
- Moment: 11:22 to 14:20 of the episode (3 min), playing on https://realalpha.app/s/most-diseases-need-treatment-tailored-to-individual-biology/; the episode from there: https://realalpha.app/v/YnV8pgHtO5Y/?t=682

## Quote

> “I really think **most diseases should be thought of as rare diseases**, because each one of our biology is different.”
> — [Priscilla Chan](https://realalpha.app/people/priscilla-chan/) at [13:23](https://realalpha.app/v/YnV8pgHtO5Y/?t=803) · a16z Podcast

## Takeaways

1. Variants can be linked to downstream cell and protein changes.
2. That link can guide targets and help predict side effects.
3. Common diagnoses may group people with different biology.

## About this segment

Priscilla Chan traces how variants affect cells and proteins to identify targets and anticipate off-target effects. She argues that common diagnoses can hide distinct biology, making individual-level treatment important.

From “Mark Zuckerberg & Priscilla Chan: How AI Will Cure All Disease”, Nov 6, 2025. [Watch the full episode](https://realalpha.app/v/YnV8pgHtO5Y/)

## Transcript

Transcribed by machine (Whisper) from the episode’s audio, so a word may be off here and there.

[11:29](https://realalpha.app/v/YnV8pgHtO5Y/?t=689) now. I'm curious what you view success as in the therapeutic realm. So, you know, we think a lot about understanding biology and sometimes we bet on startups that want to unlock completely new biological areas, diseases where we don't know what's going wrong. And then there's another group of folks who kind of say, hey, okay, now that we understand what's going wrong, let's fix it. Let's come in with a drug. Let's come in with a new type of chemistry, a new type of antibody.

[11:55](https://realalpha.app/v/YnV8pgHtO5Y/?t=715) How do you, what do you think success for the CZ Biohub? looks like 10, 20, 50 years from now in terms of the new medicines that you've enabled? We want there to be like an explosion of a community who are building these, just the new wave of what it means to be deploying precision medicine. Like, I think for rare diseases and common diseases alike, you're really talking about individual biology that we sort of lump together. And we often don't know how it happens, right? We know that you have this mutation or the worst nightmare is you have a variant of unknown significance. What does that even mean? The horrible of the U.S. Yes, horrible. And you're like, you tell someone you kind of know something, but we don't know what it means. But if you look at the way we've been able to look at variants and look at single cell transcriptomics, we're starting to be able to say, okay, this

[12:51](https://realalpha.app/v/YnV8pgHtO5Y/?t=771) variant actually impacts this set of downstream cells. And then we start looking at the proteins that get expressed and how it looks similar or different to what a healthy cell would look like. Then you can start targeting, okay, like let's look at that as a target. And you both know the specificity of the target you want to build based on the ability to connect mutation to protein expression, as well as to be able to predict off-target effects. What are the side effects?

[13:21](https://realalpha.app/v/YnV8pgHtO5Y/?t=801) Because you also know where else that drug will be able to interact with the body. And so those are rare. But I really think most diseases should be thought of as rare diseases, because each one of our biology is different. And right now, we just get lumped, right? We get lumped based on age, demographics ancestry if we're lucky to have that level of understanding but truly each one of our biology is different and say like if you look at hypertension or depression like we kind of just go by trial and error and saying like let's just try that drug and see what happens but what should really happen is being able to precisely and accurately and quickly treat people by looking at individuals biology we want to enable the basic science and we would be thrilled if people picked up the models that we build to be able to build the diagnostics, the therapeutics that need to