I think you may be confusing “genes” as in DNA with mitochondria.

Mitochondria are separate organisms that live within our cells and are a critical part of our energy production cycle.

The procedure you are likely referring to is “mitochondria replacement therapy”, in which the mother’s mitochondria are replaced with those of a 3-rd party donor.

This can be done in cases where the mother has a disease related to her mitochondrial DNA.

It’s actually been done since the 90s, the oldest human born this way is probably older than yourself. But its been banned on and off in various countries due to ethical debates.

That is, however, very far from actually mixing the DNA of 3 humans together.

Modifying DNA with precision is quite a complex procedure, even with technologies like CRISPR only a small % of the DAN can actually be modified.

Replacing mitochondria is…. rather easy, it’s just transferring cytoplasm from the “donor” egg to the “host” egg (the donor having healthy mitochondria and the host the unhealthy ones).

If this is not what you are referring to, please provide a source, I could find no information on any other “3 parent” procedure that is even remotely close to be considered for approval when it comes to human babies.

Otherwise, please don’t use buzzwords just because the media is doing it… your mitochondria are indeed part of what makes you, you. But your DNA is orders of magnitude more important, and we still can’t give babies DNA from 3+ parents.