We know that the form of RNA is based on its sequences. I would suggest that certain forms will be selected in a heat cycle. Now put the two together. That would suggest that what the heat cycle selects is a certain form - AND that all RNA with that form have similar sequences or coding. Thus logic says that what is selected in the heat cycle will be RNA's with similar coding. Thus each selected RNA will also have a similar coding while those not selected will have different coding.
The thermal cycle then selects a specific coding, because it selects a specific shape and that shape requires a specific coding.
