Hilmar, I understand your concerns. We live in a "brave new world," where advances in biotechnology take place at a breakneck pace, often with little opportunity for any kind of ethical deliberation before researchers attempt to matriculate the emerging technology to clinical settings. The new in vitro fertilization (IVF) method you reference is just one example. (The following article discusses this method and its potential promise: "Dad May Join Two Moms for Disease-Free Designer Babies.")
As tempting as it might be to condemn summarily emerging biotechnologies—particularly ones that seem ethically questionable upon first glance—it is important to take the time to understand the science behind the technology. Often times this understanding alleviates some concerns and helps provide a realistic assessment in terms of the technology's true impact on the dignity and sanctity of human life.
After working through the science that underpins this new IVF methodology, I've concluded that it is ethically acceptable from a Christian vantage point—with a few caveats. I'm excited because judicious application of this technology can go a long way toward reducing—maybe even eliminating—genetic disorders resulting from mutations to mitochondrial DNA.
For a detailed discussion of the science behind this IVF method and the reasons why I find it ethically permissible, listen to the February 26, 2014 episode of Science News Flash.