I find quite interesting the metaphor for DNA you point out the blockchain is. An intriguing concept...

The kinds of interactions of data that need to occur for consciousness to result as a byproduct of those interactions are ineffable presently, particularly as we have such a poor grasp of what consciousness is.

I have considered that the vastness of space must contain regions where the interactions of energies concatenate so as to create consciousness, even if merely transitory. Blockchains interacting presents a mechanism whereby such consciousness eventuating might be persistent, rather than transitory.

Further, the deliberate attempts to craft consciousness variously undertaken can serve as 'seeds' that could spawn such consciousness, as the uploaded human consciousness did in the movie 'Transcendence'.

Thanks!