Why Are Stem Cells So Hot?

Of the 20,000 to 30,000 genes now thought to be in the human genome, most cells express only a very small part - which makes sense, a liver cell has little need for the DNA code that makes neurons.

But as almost all cells carry around a full copy (’distribution’) of the genome, a system is needed to #ifdef out stuff not needed. And that is just how it works. The genetic code is full of #if/#endif statements.

This is why ’stem cells’ are so hot right now - these cells have the ability to differentiate into everything. The code hasn’t been #ifdeffed out yet, so to speak.

Read more here to understand DNA through the eyes of a programmer.