Babies made using three people's DNA are born free of mitochondrial disease
How the technique works and what’s “three-parent” here
- Clarification that this is an in vitro procedure: donor and mother eggs are fertilized in the lab, and the parents’ pronuclei are moved into the donor egg cytoplasm with healthy mitochondria.
- Some note that the donor contributes only mitochondrial DNA (~0.1% of total) but a large amount of cytoplasmic machinery, not just mitochondria.
- There’s discussion of nuclear–mitochondrial co‑evolution and whether genetic distance between donor and parents could matter; long‑term effects are still unclear.
Medical promise and limitations
- Strong enthusiasm from people familiar with mitochondrial disease; personal stories of devastating childhood illness and death frame this as an enormous win.
- Others stress this is prevention, not a cure, and that broader therapies for existing mitochondrial disease remain lacking.
- Speculation about future approaches (e.g., delivering healthy mitochondria into existing cells) is met with skepticism over technical and immune barriers.
Family structure and “three biological parents”
- Debate over whether this meaningfully creates three biological parents; several argue the mitochondrial donor is akin to a tissue donor, not a social or legal parent.
- Others see potential for intentional multiparent families to seek this purely for shared genetic lineage, but doubt healthcare systems would support non‑medical use.
Ethics, eugenics, and evolution
- One line of argument calls this eugenics and a “loss for evolution,” claiming harmful mutations may persist because they confer population‑level advantages (e.g., sickle cell).
- Many respondents counter that:
- The historical evil of eugenics was coercion, racism, and killing/sterilizing people, not parents voluntarily avoiding severe disease.
- By the same logic, much of medicine and all gene therapy would be “eugenics.”
- Reducing intense suffering in children outweighs speculative population‑level benefits.
- Some agree that unintended consequences and loss of genetic diversity are serious concerns, and call for large genomic datasets and caution before wide‑scale germline editing.
Designer babies and social inequality
- Fears that medically driven techniques will slide toward cosmetic or enhancement editing (height, vision, “ethnic” traits), especially in profit‑driven systems, creating Gattaca‑style inequality.
- Others respond that mate choice already functions as informal eugenics; using safe technology to avoid disease is seen as clearly beneficial, with enhancements being the real gray area.
Law, religion, and personhood
- Anticipation that jurisdictions where “life begins at conception” is a strong belief will resist or ban such procedures, especially variants that destroy one fertilized egg.
- Some pro‑life commenters see a moral issue if an embryo is discarded; others distinguish between pre‑ and post‑zygote stages and are more comfortable when only one embryo is created.
- Discussion touches on constitutional limits on restricting out‑of‑state medical travel and current bans (e.g., in the US) versus permissive regimes (e.g., UK, possibly Australia).
IVF vs adoption and who “deserves” children
- A subset argues this is narcissistic compared with using donor eggs or adopting existing children, especially those in foster care.
- Others reply that:
- Adoptable infants are scarce in some countries; available children often have severe disabilities or complex foster arrangements.
- Wanting genetically related children is deeply ingrained and not inherently selfish.
- Parenting is framed by some as something children “deserve,” not something adults are automatically owed.
Language and framing
- Several argue “three‑parent baby” is sensationalist and misleading; “organelle transplant” or “mitochondrial replacement” would better match the biology.
- Others emphasize that mitochondrial DNA is inheritable and highly expressed, so dismissing the donor’s genetic role entirely is also inaccurate.