Up to 40% of natural conceptions are spontaneously aborted, often before a woman knows she's pregnant. This is typically the body's way of rejecting embryos with severe genetic abnormalities. This natural process provides a powerful biological precedent for the practice of pre-implantation genetic screening.
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Many object to embryo selection because they mistakenly believe it involves altering genes. In reality, the technology simply reveals information about natural genetic variations already present in IVF embryos, allowing parents to choose, not tinker.
The controversy and business opportunity in polygenic embryo selection lie in interpreting genetic data, not in the physical sequencing. Companies are competing on the quality and scope of their predictive models for health and traits, which they apply to data from established lab processes.
In the U.S., support for embryo screening for disease is nearly double that for intelligence, while in Singapore, support is equal. This gap is attributed to Western taboos from WWII-era eugenics, creating a moral distinction between selecting against negative traits and for positive ones that is less pronounced elsewhere.
The predictive power of embryo screening can be validated without controversial longitudinal studies on children. By testing if models can accurately predict trait differences between adult siblings using only their DNA, companies can prove efficacy for embryos, who are essentially unrealized siblings.
A new innovation allows companies to construct an embryo's entire genome using raw data from a standard Down syndrome test. This means parents can get comprehensive polygenic reports without needing explicit approval from clinics or doctors, effectively democratizing access and removing traditional medical gatekeepers.
Standard IVF practice involves a doctor visually selecting the embryo that appears most "normally shaped." This is already a form of selection. Polygenic screening simply replaces this subjective "eyeballing" method with quantitative genetic data for a more informed choice, making it an evolution, not a revolution.
Polygenic embryo screening, while controversial, presents a clear economic value proposition. A $3,500 test from Genomic Prediction that lowers Type 2 Diabetes risk by 12% implies that avoiding the disease is worth over $27,000. This reframes the service from 'designer babies' to a rational financial decision for parents.
The ability to select embryos fundamentally changes parenthood from an act of acceptance to one of curation. It introduces the risk of "buyer's remorse," where a parent might resent a child for not living up to their pre-selected potential. This undermines the unconditional love that stems from accepting the child you're given by fate.
Fears about unintended trade-offs from embryo selection are largely unfounded due to 'positive pleiotropy.' The genes for many diseases are positively correlated. This means selecting against a disease like severe depression often provides a 'free' reduction in the risk of other conditions like bipolar disorder and schizophrenia.
The complaint 'I would have been selected against' is logically incoherent. Any change in conception—including embryo selection—creates a different person. One cannot be 'harmed' by a choice that results in their non-existence; they are simply replaced by another potential person. The complaining 'you' would never have existed.