Revolutionary Science or Unprecedented Risk? – Watts Up With That?

The recent discussion paper published in Science by Adamala et al. examines an emerging frontier of synthetic biology: the creation of “mirror life.” This concept involves organisms composed entirely of mirror-image biological molecules, a departure from the homochirality seen in all known life. While the field holds tantalizing possibilities, the paper paints a sobering picture of the dangers that mirror life could unleash.

What is Mirror Life?

In biological terms, “chirality” refers to the handedness of molecules, akin to how our left and right hands are mirror images but not superimposable. In nature, life is homochiral—DNA and RNA are right-handed, while proteins are left-handed. Scientists, however, are on the cusp of being able to synthesize entire organisms made from molecules with reversed chirality. These mirror organisms, if realized, would operate entirely outside the framework of Earth’s biological ecosystem.

The Allure of Mirror Life

The potential applications are significant. Mirror molecules resist degradation and immune responses, opening possibilities for more durable drugs and innovative therapeutics. They could also aid in basic research and provide insights into the origin of life. Yet, as the paper stresses, the creation of mirror organisms goes far beyond these applications and risks unforeseen consequences.

A Pandora’s Box of Dangers

The discussion paper underscores several critical risks posed by mirror life, particularly mirror bacteria. The authors write:

“Our analysis suggests that mirror bacteria would likely evade many immune mechanisms mediated by chiral molecules, potentially causing lethal infection in humans, animals, and plants. They are likely to evade predation from natural-chirality phage and many other predators, facilitating spread in the environment.”

Furthermore, the paper highlights the invasive potential of mirror organisms:

“We cannot rule out a scenario in which a mirror bacterium acts as an invasive species across many ecosystems, causing pervasive lethal infections in a substantial fraction of plant and animal species, including humans. Even a mirror bacterium with a narrower host range and the ability to invade only a limited set of ecosystems could still cause unprecedented and irreversible harm.”

The authors express particular concern about the ability of mirror bacteria to bypass natural containment mechanisms, stating:

“Biocontainment and biosafety approaches might be proposed to reduce these risks.
…
However, escape from these safeguards through evolution or human error could occur. Multiple auxotrophies would reduce but not eliminate the chance of escape.”

Why Pursue It?

Despite the alarming risks, the benefits of creating mirror organisms seem relatively limited. Alternative methods can already produce mirror biomolecules for therapeutic and scientific purposes without constructing living mirror cells. As the authors argue:

“Foreseeable benefits of the creation of mirror bacteria are limited. Mirror biomolecules have scientific and potential therapeutic applications that are worth pursuing; however, although mirror bacteria could plausibly help to manufacture them, such molecules can be made through other means.”

A Call for Precaution

Adamala et al. propose several urgent measures:

• Banning research aimed at creating mirror organisms.
• Enhancing oversight and regulation of enabling technologies.
• Monitoring purchases of materials essential for synthesizing mirror molecules.
• Convening global discussions to align governance strategies.

The paper concludes with a call for action:

“Unless compelling evidence emerges that mirror life would not pose extraordinary dangers, we believe that mirror bacteria and other mirror organisms, even those with engineered biocontainment measures, should not be created. We therefore recommend that research with the goal of creating mirror bacteria not be permitted, and that funders make clear that they will not support such work.”

A Responsible Path Forward

Mirror life research epitomizes the dual-use dilemma in science—technological advances that promise benefits while simultaneously posing severe risks. As we stand on the brink of realizing such life forms, the choices we make now will determine whether we safeguard the planet or unleash a biological revolution fraught with peril.

This discussion paper is not merely a warning; it is a plea for global foresight and action. The stakes are high, and the time to act is now.

H/T Roger Pielke Jr.