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Betül Kaçar

👤 Speaker
1813 total appearances

Appearances Over Time

Podcast Appearances

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

amino acids.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

So we use six life uses 64 possible states minus four of the starts and stops to code for 20 amino acids in different combinations.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

That is really amazing.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

If you think about there, there are 500 different amino acids life can choose, right?

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

It's,

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

Narrowed it down to 20.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

We don't know why.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

A lot of people think about this genetic code is quite fascinating.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

So far, right?

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

I mean, it didn't do it for 4 billion years.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

I don't know.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

We may wait for another 4 billion years.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

We don't know.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

So we would be fooling ourselves if we said we know exactly how many amino acids existed early on.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

But there's no reason to think that it wasn't the same.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

Yeah.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

We don't have a good reason.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

But because roughly 20 out of 60 states are used, you're using one third of your possible states in your information system.

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

So this may seem like a waste, but informatically it's important because it's abundant and it is redundant, right?

Lex Fridman Podcast
#350 – Betül Kaçar: Origin of Life, Ancient DNA, Panspermia, and Aliens

So this code degeneracy, you see this in, that's implemented by this translation machinery inside the cell.