From 20 15 to 10, British legislation came into effect, which legalized the technology and became the first country in the world to allow three-parent test-tube babies to be conceived by two genetic mothers and a genetic couple.
Three-parent parenting technology is similar to artificial conception and IVF, but there are differences. Combine parents' genes with healthy mitochondria of female donors. Through IVF, parents' genes are combined with donated eggs to create "better" babies. The genes introduced from donated eggs only account for 0. 1% of the total genes of the baby, and will not affect the appearance and other characteristics of the baby.
Many genetic diseases begin with mitochondrial gene defects, and mitochondria exist in almost every cell of human body. Nowadays, one in every 6,000 babies in the world has a mitochondrial gene defect, and the "three-parent parenting" technology can reduce the risk of mitochondrial genetic diseases (data from the Internet). Defective mitochondria passed from mother to baby will make human cells lack energy, which may lead to muscle weakness, blindness, heart disease and congenital disability. This medical technology is to avoid mitochondrial genetic diseases.
As for moral issues, I don't think it will affect them. After all, it's just genetic improvement, not surrogacy.