When does trying to have a healthier baby become eugenics-y?

Dear Expecting, you have recently undergone in vitro fertilization (IVF) and currently have multiple embryos. Your fertility clinic suggests using preimplantation genetic testing for aneuploidy (PGT-A) to screen for conditions like Down syndrome and determine the sex of each embryo. You are also considering more advanced polygenic testing, which can assess various genetic traits, including height, IQ, and the likelihood of certain diseases.

While it may seem tempting to choose the embryo with the most desirable traits, such as a healthier child or increased intelligence, there are several important factors to consider. Firstly, polygenic testing is not as accurate as it claims to be. The risk reduction estimates are often overstated due to statistical assumptions, potentially leading to confusion and misinformation among consumers.

Secondly, the concept of "better" or "healthier" is subjective. Mental health conditions, such as depression and anxiety, are complex and may not always be negative. In fact, some levels of anxiety could be linked to creativity and other positive traits. Additionally, mental health conditions often exist on a spectrum, and removing mild or moderate symptoms might have unforeseen consequences.

Furthermore, pleiotropy refers to the phenomenon where a single gene can influence multiple traits. Selecting embryos based on polygenic testing may unintentionally eliminate genes that are linked to desirable traits, potentially reducing the variety of traits in future generations.

In conclusion, the desire to have a healthy and happy child is a natural and admirable aspiration. However, it is crucial to approach genetic testing with caution and a clear understanding of its limitations. Rather than focusing on specific traits, parents should prioritize their child's overall well-being and happiness, embracing the uniqueness of each individual.