Before explaining how one baby can now have three different individual parents, it is important to understand in vitro fertilization (IVF) and how the eggs and sperm are cultivated in what is basically a petri dish until fertilization occurs. After fertilization occurs and the right number of cells are formed after multiplying through, the "egg" is implanted back into the mother where it can go through the regular developmental stages that it usually would go to with normal sexual fertilization.
A picture of the doctor from the procedure holding the baby.
The family that had this procedure done in Mexico already suffered from two miscarriages from the same issue. The mitochondria of the mother are diseased and cannot support a new life even though they are supporting the mother's life. So through the use of this method, a family was able to avoid it's third miscarriage due to a little bit of creativity with the IVF technique.
"This method involves removing the nucleus - the bulk of a cell's DNA - from one of the mother's egg cells, and inserting that nucleus int a donor egg cell stripe of its own nucleus. The result f an egg with mitochondrial DNA from a healthy donor and nuclear DNA from the mother. Five donors eggs prepared this way were then fertilized with the husband's sperm - but only one of the resulting embryos had a normal number of chromosomes. That embryo was transferred into the mother-to-be."This relates to our genetics class because of the idea of where DNA is in a cell. In all Eukaryotes, the areas where DNA is present are in the nucleus of the cell and within the mitochondria or chloroplasts. In animals cells, we only have the mitochondria instead of the chloroplasts. With this said, the father's genetic material from the sperm, the mother's genetic material from her mature ovum, and the donor's mitochondrial DNA were all contributing to the genome of the child, which is why the child is considered to have three separate parents. What is interesting as well is technically speaking the child will only show the traits of the original mother and father since the mitochondrial DNA goes back many years ago to that first endosymbiont. The child will phenotypically show traits from the original two parents, but in it's genome is the DNA of all of the three parents. I think this is a wonderful push for science and genome adjustment based on diseases possible children may inherit and possibly will catalyze the FDA to chill out and loosen there standards here in the United States so that our country can get some credit for scientific advancement.