In-vitro fertilization (IVF) is a technology that involves the fertilization of egg and sperm outside of the human body. It is primarily used as an alternate conception method for women or men struggling with infertility. For those who risk passing on a hereditary disease, pre-implantation genetic diagnosis (PGD) allows these individuals to select embryos that do not carry genetic mutation for the disease and possibly conceive a baby that is completely healthy. While the technology can be hailed as beneficial for the future of human reproduction, questions arise about its potential use for non-medical purposes, such as profiling embryos for desirable traits. What does a "healthy" baby constitute? Are there reliable methods for predicting the future physical appearance of an embryo or even complex traits such as intelligence? Recent news suggest IQ profiling for embryos is just around the corner. Consider the following sensational headlines in online blogs and popular newspapers:
Those who worry, fear not – based on what we currently know, many of these desirable traits that include intelligence and IQ levels, physical appearance, and personality traits are not predominantly dependent on DNA. PGD works when detecting an embryo that does not carry a hereditary disease because these are easy to detect genetic mutations. The personality traits listed above are shaped through complex interactions of genetics and the environment. We cannot predict with 100 percent certainty the impact of environment on gene expression once the fetus grows and a baby is born, making it seemingly impossible in today's world to manufacture a baby with superior intelligence.
Some companies plan to offer "polygenic scoring" of IVF embryos to identify and prevent the implantation of embryos that are likely to have very low IQs. It is claimed that, in the future, this method would allow to predict with a great precision a child’s intelligence, athletic skills and other desirable traits, alongside disease heritability. Most research in genomic medicine, however, indicates that this is highly unlikely to occur and the method is currently shown to be only accurate for detecting heritable diseases.
If it were to be true, embryo profiling for intelligence can be seen as unethical. If intelligence level is dependent on both genetics and the social environment, many environment enriching factors for children, such as after school programs and private tutoring, already carry a hefty price tag. Access to environments that provide optimal conditions for upbringing children is determined by socioeconomic status and is increasing in cost day to day. PGD is an expensive method as it is and so is IVF – funding research for these expensive procedures should continue to focus on finding ways to detect health risks and diseases. Allowing the use of PGD for human enhancement not only treads a dangerous line between parents' wishes and the limits of genetic manipulation, but will also have negative consequences for populations with low socioeconomic status.