mitochondrial DNA comes only from the mother.
Nobody fully understands why or how fathers’ mitochondrial DNA gets wiped from cells. An international team of scientists recently studied mitochondria in the sperm of a roundworm called C. elegans to find answers.Their results, published this week in the journal Science, show that paternal mitochondria in this type of roundworm have an internal self-destruct mechanism that gets activated when a sperm fuses with an egg. Delaying this mechanism, the scientists found, led to lower rates of embryo survival. Down the road, this information could help scientists better understand certain diseases and possibly improve in vitro fertilization techniques.
HOW IT'S POSSIBLE FOR A BABY TO HAVE THREE PARENTS
it's a genetics thing---a particular method of in vitro fertilization that inserts parts of one woman's cells into a second woman's egg. Specifically, the procedure replaces via transplantation the birth mother's mitochondria---the energy-making power plants of every cell that have their own DNA, separate from the DNA that builds the rest of the body
The fertilizational three-way starts out with two sets of eggs, one set from a mother with errors in her mitochondrial DNA. Then we take eggs from another woman, a donor whose mitochondria is free from the mutations.Using high-powered microscopes, microsurgical needles, and lasers, physicians remove the nucleus from each cell with the mitochondrial problems. We keep the nuclei from the donor female, and place them in the cytoplasm from the other donor.