'Early' Genetic Foundation for 'Later' Genetic Expression ["Templates"]

Maybe this is the 'wrong' NG.
I imagine the 'mammalian diving reflex' and 'sweating' may be earlier
developments than 'other, later' developments.
Therefore, I imagine that 'later' genetic changes may use 'earlier'
developments in the genome as 'reference points' for their [the later ones]
activity.
Thus, therapies or changes to genes that are 'earlier' forms may have
consequences in the expression of 'later' forms.
Anyone got a URL on this?



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