The U.S. Congress effectively banned the human testing of gene-editing techniques (think CRISPR) that could produce genetically modified babies. The bill also is being applied to mitochondrial replacement therapy, a treatment that prevents the transmission of debilitating or even deadly mitochondrial disorders to children. “Mitrochondria are the components of a human cell responsible for producing energy. They also have their own DNA, separate from the DNA in the nucleus. Babies always inherit their mother’s mitochondrial genome. Mutations in the mitochondrial genome, in the nuclear genome, or both can lead to a wide range of mitochondrial disorders, many with severe and even debilitating symptoms.” Read on.