disease and identify new treatments for disease. If you could take any cell in the body and

turn it into this immature stem cell-like state, if you could do it for animals you

could also do it for humans -- and if you could do it for humans, you could do it for

patients. And automatically, you have the ability to study the cellular and the molecular

basis of a person's disorder. And that's exactly what's happened over the last 6 or 7 years.

Human induced pluripotent stem cells, which is what we call them now, iPS cells, then

you can use these cells as a disease-in-a-dish, in order to identify new treatments. And you

can determine whether they might have adverse effects in the dish -- even before they go

into patients. People have been able to generate these cells from people with schizophrenia,

people with autism, people with bipolar disorder. And its really opened up a whole new world

of investigation to us. There are other ways in which people have been able to harness

an amazing capacity of these cells to self-organize into structures that look like the organs

that are in your own body. Recently there have been studies that have used these cells

to develop what are called organoids. And that sounds very science fictiony and Frankenstein-like.

But what they are is they are structures that the cells make all by themselves -- with a

little bit of coaxing from the scientists -- but they look like miniature brains. And

they have the organization of the brain. They have the cell types that are very similar

to the cell types in the brain, in the right organization. What that does is that allows

you to look whether the organization of these structures differs between cells from normal

non-disease subjects versus patients. And that's important for diseases like schizophrenia,

because the evidence suggests that these are developmental disorders. And to be able to

recapitulate -- to show the developmental process all over again -- in a dish is an

incredibly powerful tool. And allows you to discover whether there are mechanisms that

aren't functioning properly in these developing structures from patients. And it allows us

to look, in very fine detail, about what the exact defects are in disorders like autism

spectrum disorders, schizophrenia, bipolar disorder. Because all of these disorders fundamentally

are disorders of communication between these cells -- not just individually, but in circuits.

Because, fundamentally, these disorders are circuit disorders. The question is whether

you can actually recapitulate a predictive model of diseases using these simplistic cultures.

Where this technology will have the most relevance is not so much a doctor taking a cell or tissue

from a patient and turning it into cells -- because those technologies, or those procedures, will

take too long. You wouldn't be able to necessarily do a test on an individual patient using their

own cells. What you can do is understand the rules of the game. Are there certain patients

with say, a certain set of genes, a certain variant of genes, which would allow them to

respond in a certain way to particular drugs, while other patients who might have the same

disease may not respond in exactly the same way. So once you understand fully the genetics

of particular disorders, then you can use these cells to develop a whole set of drugs

that are based on whether they have a certain set of gene variants versus another set of

gene variants, then we come to a world of precision medicine. It's not personalized

medicine, in which a drug is tailored to any individual -- but it's a world in which you

can say "because you show these certain set of genes, you're more likely to respond to

drug X rather than drug Y." And you can develop diagnostic tests based on that.