Human Genome
© Nature
Human chromosomes, with segments containing at least two genes whose order is conserved in the mouse genome as colour blocks. Each colour corresponds to a particular mouse chromosome. Centromeres, subcentromeric heterochromatin of chromosomes 1, 9 and 16, and the repetitive short arms of 13, 14, 15, 21 and 22 are in black.
It's only been 13 years since scientists at National Human Genome Research Institute finished sequencing the human genome, but now another group of American scientists are calling for a 10-year project aimed at creating their own human genomes from scratch.

The proposal for the project, known as the 'Human Genome Project—Write', was published in Science last Thursday and announced the group's intention to launch the project this year with the $100-million it will secure in funding.

As argued in the paper written by 26 prominent geneticists, HGP-Write is the logical continuation of the Human Genome Project, which successfully sequenced 99.9 percent of all the DNA humans have in common, otherwise known as the human genome.

"Genome synthesis is a logical extension of the genetic engineering tools that have been used safely within the biotech industry for ~40 years and have provided important societal benefits," the authors wrote in the paper.

"HGP-write will require public involvement and consideration of ethical, legal, and social implications (ELSI) from the start. Responsible innovation requires more than ELSI, though, and involves identifying common goals important to scientists and the wider public through timely and detailed consultation among diverse stakeholders."

The ostensible aim of the project would be to reduce the cost of engineering large DNA sequences in labs by over 1000 times in 10 years.

This could lead to important biotech innovations like growing human organs that could be used for transplants, and cell lines that are engineered to be resistant to viruses and cancers.

Although the authors acknowledge their proposal is "ambitious" and given the current cost of genome sequencing likely to be very expensive, they expect technology to advance in tandem with the project, drastically reducing its cost over time.

"Total project costs are difficult to estimate but would likely be less than the $3 billion cost of HGP-read," they wrote.

A reduction 1000-fold reduction in the cost of engineering DNA sequences might sound overly optimistic, but there is a historical precedent. In the 15 years since the original Human Genome Project began, the cost of sequencing an entire human genome has dropped from $100 million to around $1000 today—a 100,000-fold decrease. By comparison, a 1000-fold reduction in cost seems pretty modest.

The authors cite the success of engineering small bacteria and virus genomes from scratch as an example of the feasibility of their project, but so far these are the only genomes that have been manufactured by humans. Still, the paper's authors are optimistic and the success of HGP—Write, they argue, would have far reaching implications beyond human health.

"DNA synthesis, like sequencing and computation, is foundational technology," the authors wrote in the paper. "HGP-write could also facilitate biological engineering of many organisms, accelerating R&D across a broad spectrum of life sciences and supporting basic R&D of new bio-based therapies, vaccines, materials, energy sources, disease vector control, and nutrition."

The project would develop over the course of several pilot projects before trying to tackle the human genome. For example, researchers would first try to construct specific chromosomes or all the genes needed to make a particular kind of cell.

Despite the optimism of the paper's authors, not everyone is so thrilled with the idea of engineering human DNA in a lab. The plan has drawn criticism from a number of quarters, not only for the secrecy that surrounded the discussions leading up to the publication of the paper on Thursday, but also because it could theoretically lead to the creation of children without biological parents in the future.

As Stanford bioengineer Drew Engy and Northwestern professor of religion Laurie Zoloth wrote in a recent op-ed for Cosmos Magazine, "just because something becomes possible, how should we approach determining if it is ethical to pursue?"

Still, the general opinion of the genetics community seems to be in favor of the project.

"The project is not as controversial as some observers might be saying," said John Ward, a professor of synthetic biology at University College London. "We already replace segments of human genes in cells growing in culture dishes. This is well regulated and is the very core of the new advances in medical genetics. There is no call to make an entire human being just as there is no push for doing that with current studies using human embryos."