You're not wrong, it's a mixture of epigenetic changes, and local environment changes. As a cell differentiates, it definitely changes its epigenome. These chan

You're not wrong, it's a mixture of epigenetic changes, and local environment changes. As a cell differentiates, it definitely changes its epigenome. These changes are also mediated by cell-cell interactions, and other morphogenic proteins, for example, the SHH gene: https://en.wikipedia.org/wiki/Sonic_hedgehog https://en.wikipedia.org/wiki/Sonic_hedgehog