Not as such, but there are RAM-based cartridge copiers such as the Super Magic Drive and Magic Drive Plus. These copiers have a floppy drive interface so you can save and load ROM images, and a parallel interface to link to a PC.
It's only relatively recently that Flash-based memory has become cheap enough to use for this purpose - back in the Genesis's heyday, it would have been far too expensive.
In terms of a homebrew project, though, it's certainly possible.
Mike