When Duke University scientists recently modified mice with human DNA, resulting in mice with larger brains, we learned something new about what makes humans unique. But does this discovery tell us anything about the way humans are made in the image of God?
The sequence of a person’s DNA largely determines the biological make up of that person, yet discovering which part of the DNA gives us uniquely human traits is quite a challenge. Debra Silver and her colleagues at Duke were exploring what sequences are unique to the human genome that might explain our intellectual capacity.
The researchers sought to test the role of a human-specific DNA sequence thought to control a gene involved in brain development. To do so, they modified the mouse genome to contain the human sequence. The developing mouse embryos had larger brains, up to 12% larger than controls. While these results offer a fascinating clue as to what makes us genetically unique, the experiments do pass into an ethically questionable area. As one bioethicist told NPR, "The prospect of, sort of, tearing down the barriers between humans and other nonhuman species in ways that really threaten our sense of ourselves as special is disturbing."
The image of God has to do with our calling as stewards of God’s creation.
But of course we know what it is that makes us special, and it is not a bit of regulatory DNA. We are made in the image of God. The idea that we might be able to reconstruct this unique characteristic in a mouse reminds me of the Ship of Theseus. The Ship of Theseus is an ancient thought experiment about a Greek ship that sailed for many years. Over time it was repaired and updated so that eventually every board was replaced. The question is then, is it still the Ship of Theseus? Moreover, if another ship was made from all of the original boards, what would that ship be? So, how much human DNA can we put into a mouse before it is too human?
I think these sorts of questions miss the point by focusing on material instead of function. The image of God is not a material description; it is a description of our function or calling. In this sense perhaps the Ship of Theseus remains the Ship of Theseus if it continues to sail the Mediterranean full of young Greeks. The image of God has to do with our calling as stewards of God’s creation. There is no gene that carriers this designation. There is no degree of brain development that is a threshold for God’s image.
The “barriers between humans and other nonhuman species” that are most important have to do with how we carry out God’s will to creation and how we channel creation’s praise back to God. This should make us think again about human DNA sequences and mouse genomes. Is it good stewardship to do these sorts of experiments? We must remember that Jesus Christ is King, ruler and protector of these mice and all of creation. If the research being done works toward wholeness, goodness and life, it may still be good stewardship. It is not our responsibility to come up with iron-clad rules about right and wrong, but to use wisdom, Scripture and prayer to discern the will of the Holy Spirit.
So together then, let’s find wisdom. Do you think this kind of research is worth the ethical stretch if it helps us understand brain development and brain disease? Should we be uncomfortable altering the genomes of mammals? Should we worry about physically representing the image of God? Could we accidently share it with a mouse?