Should We Synthesize a Human Genome?

By Drew Endy & Laurie Zoloth
10 May 2016
At Harvard today an invitation-only group of mostly scientists, lawyers, and entrepreneurs,
~150 in total, met to discuss if and how to synthesize from scratch an entire human genome –
the heritable genetic material that in nature is transferred from parents to children. The
meeting was originally organized to focus on “deliverables and industry involvement” with
the primary goal of the project being “to synthesize a complete human genome in a cell line
within a period of ten years.”
Synthesis refers to the construction of a genome starting from simple chemicals. Such a
synthetic genome could then be tested in a laboratory by replacing the existing genome
within a human cell. All this would still be far removed from making a synthetic human.
However, the possibility of making a human cell whose genome is realized from only digital
information and raw materials should trigger broader considerations.
For context, total synthesis of a human genome has become plausible at an accelerating
rate. Thanks to new production techniques developed since 2003 the cost of assembling
the genetic material encoding genes, the “building blocks” of life, has decreased from
four dollars to just three cents per individual letter or “base pair” of deoxyribonucleic
acid (DNA). As a result, the estimated initial cost of printing the DNA fragments
encoding a 3 billion base pair human genome has dropped from $12 billion to $90
million. If cost reductions continue apace this price would approach $100,000 within 20
years. However, such dramatic additional cost reductions might never be realized without
overwhelming demand.
Advocates of synthesizing a human genome therefore argue that some open, collaborative
“grand challenge” is needed to drive development of such technologies. While we
strongly agree that sustained improvements in DNA construction tools are essential for
advancing basic biological science and improving public health we are skeptical that
synthesizing a human genome is an appropriate demand driver. We recall how
controversies associated with many of the earliest genome synthesis projects produced
unintended consequences. For example, a project that made polio virus from scratch in
2002 led to cancelled public funding for DNA synthesis research, unwittingly hindering
research across diverse and unrelated fields, as policy makers struggled to imagine how
such a technology could ever be controlled. From a simple technical perspective, we
argue that synthesis of less-controversial and more-immediately useful genomes and also
greatly improved sub-genomic synthesis capacities (e.g., real-time plasmid printing)
should be pursued; alternatives that would deliver broad and diverse benefits.
Other topics on today’s agenda included changing the human genome itself. For example,
viruses? They likely could, for purely beneficial purposes, but what if others then sought


to synthesize modified viruses that overcame such resistance? Might doing so start a
genome engineering arms race? And, what of even greater changes that can be
imagined? In a world where human reproduction has already become a competitive
marketplace, with eggs, sperm and embryos carrying a price, it is straightforward to
brainstorm various uses of human genome synthesis capacities. For example, would it be
OK to sequence and then synthesize Einstein’s genome? If so how many Einstein
genomes would it be OK to make and install in cells, and who would get to make and
control these cells? What if the project was a joint collaboration between Israel and Iran?
Returning to our primary question, just because something becomes possible, how should
we determine if it is ethical to proceed?
take place without open and advance consideration of whether and under what
circumstances it is morally right to proceed. When the first actors at the table mostly have
a significant material interest in proceeding, everyone, not just those in the room, risks
interest, and temptations to manipulate human subject consent. Pluralistic, public, and
deliberative discussions are instead the best appropriate way to frame paths forward.
In closing, we note that the narrative of creation of the human is the central narrative for
of lawyers and regulators alone. The perspectives of others including self-identified
skeptical of synthetic biology’s claims, should also be included. The creation of new
Drew Endy, Associate Professor of Bioengineering at Stanford University and President
of the BioBricks Foundation, is the author of “Synthetic Aesthetics: Investigating
Synthetic Biology’s Designs on Nature” and co-founder of Gen9, Inc., a DNA
construction company. Laurie Zoloth, Professor of Religious Studies, Bioethics, and
Medical Humanities is the past president of both the American Academy of Religion and
the American Society for Bioethics and Humanities.