Human reproduction is about to undergo a radical shift. Embryo selection, in connection with In-vitro fertilization (IVF), will help our species eliminate many genetic diseases, extend healthy lifespans, and enhance people’s overall well-being. Within 20 years, I predict that it will supplant sex as the way large numbers of us conceive of our children. But while the embryo selection revolution will do a lot of good, it will also raise thorny ethical questions about diversity, equality and what it means to be human–questions we are woefully unprepared to address.
IVF for humans has been around since 1978, the year Louise Brown, the first so-called “test-tube baby,” was born in the UK. Since then, nearly six million infants around the world have been conceived via IVF, with the procedure growing in popularity each year. Starting in the 1990s, doctors began using pre-implantation genetic screening (PGS) to extract cells from early-stage embryos and screen them for simple genetic diseases.
At present, over a thousand such diseases, including cystic fibrosis, Huntington’s disease, Tay-Sachs, sickle-cell anemia, and Duchenne muscular dystrophy, can be screened during PGS and is growing constantly. With this information, parents using IVF and PGS can select embryos not carrying those diseases if they choose to do so. Some jurisdictions, including the US, Mexico, Italy, and Thailand also allow parents to select the gender of their future children.
These are still the early days of PGS. The process of linking single gene mutations to specific diseases has been slow and painstaking, but also relatively straightforward. As increasingly more people have their full genomes sequenced, an essential foundation for the future of personalized medicine, scientists will be able to uncover and screen for genetic and epigenetic patterns underpinning far more genetically complex diseases like epilepsy and type 1 diabetes.