Prenatal genetic screenings are an essential part of monitoring a fetus’ health and expected life quality for many mothers. These screenings typically occur during the first and second trimesters of pregnancy and involve less invasive testing of maternal serum which is followed by amniocentesis or chorionic villus sampling, at the event of a positive screen. One of the many abnormalities detected by prenatal testing includes Down syndrome, the most prevalent genetic disease involving intellectual disability, which results from an extra whole or partial copy of chromosome 21.
In Iceland, up to 85% of pregnant women decide to undergo prenatal genetic screenings for Down syndrome, with a nearly 100% termination rate when Down syndrome is detected. Additionally, from 2007 to 2017, an average of two to three children with Down syndrome were born each year in Iceland. In the United States, the majority of pregnant women who screened positive for Down syndrome also opted for termination, with a rate between 67% and 85%.
As prenatal screenings in pregnancies with Down syndrome are quite prevalent, Ashley Brandebura has researched the brain molecule pleiotrophin’s role in Down syndrome. Brandebura’s work offers another perspective on Down syndrome intervention. Dr. Brandebura, a researcher at the University of Virginia, has determined that the delivery of upregulated pleiotrophin in adult mice with Down syndrome results in improved function of faulty neuronal circuits.
While Brandebura’s work cannot be applied to human therapeutics just yet, it establishes that adult mice with Down syndrome were able to have rescued dendrite morphology and reduced synaptic plasticity defects. Faulty dendrite morphology and synaptic plasticity indicate structural issues in neurons, and these issues in neuronal architecture are associated with intellectual disability. If further research suggests that these findings are therapeutically transferable to humans, the cognitive function and quality of life of those with Down syndrome could be improved, even after developmental stages.
The quality of life and health of those with Down syndrome is what drives much of the discourse regarding prenatal and postnatal interventions, so how much does Down syndrome affect overall well-being? A study conducted in Italy determined that parents of children with Down syndrome have differing perspectives on how the disorder affects their child’s life. Overall, parents reported high levels of emotional well-being in their children, especially those with greater adaptive strategies and IQ. However, the physical wellness aspect of quality of life was lower, as many with Down syndrome experience comorbidities such as autoimmune diseases, congenital heart disease, and hypothyroidism. Additionally, it is important to note that the parents of these children were denoting their quality of life, not the children themselves, so it is difficult to determine how those with Down syndrome perceive their well-being.
While the argument can be made that Down syndrome detriments the quality of an individual’s life, there are many cases where this is not observed and people with Down syndrome lead happy, fulfilling lives. In the light of new discoveries that have implications for postnatal treatment and the variability in quality of life; could the prenatal termination of pregnancies with Down syndrome be considered eugenics?
Eugenics reflects the idea of intervention in reproduction that aims for the heritability of only “desirable” traits. While some might view the abortion of fetuses with Down syndrome as medically necessary or justified, due to the comorbidities, cognitive deficiencies, and social rejection associated with the disease, others might argue that the genomic disorder does not impair well-being enough to warrant termination. Individuals with Down syndrome can lead fulfilling lives, as the degree that this chromosomal abnormality impacts people is variable. With one study describing adults with Down syndrome as having higher levels of independence and social contact compared to those with autism spectrum disorders, the type of impairments that justify prenatal involvement becomes problematic.
There are murky ethical boundaries for terminating a pregnancy on the basis of saving a child from a life of misery, especially when quality of life is variable and new research might point to beneficial therapies. As the development of prenatal testing and gene therapies continues to develop, we must consider where we draw the line between altruistic scientific advancement and unethical intervention that eliminates the diversity of humankind.