[thedoc (OP)]

Dalton Seymour asked the Naked Scientists:
   
I have been trying to imagine how the genetic sequence of chromosomes might be structured to control the decreasing potency of embryological stem cells such that they become increasingly specialized and eventually differentiate into specific tissue and cell types.

In particular, as it might apply to the growth of the brain, specialization of regions, and cell types. I'm interested in even plausible guesses about this and the possibility that the telomeres may be part of the control mechanism.

What do you think?