As our comrade Justin has pointed out repeatedly, the expression of genes depends on some existing environmental conditions; by themselves, genes can do nothing. This is true from the moment of conception. Thus there is nothing "prior" to genetic factors (remember the womb is an environment too!).
> The strands woven together metaphor doesn't contradict the notion of a
> biologically independent strand that exists before the other strands in the
> ontogeny of an individual.
Is it biologically impossible for a "biologically independent strand" to exist prior to and independent of the environmental conditions in which the biological strand is expressed. C'mon, embrace the dialectic here!
Miles