'The future of the human race': Scientists call for temporary global ban on gene-edited babies

Gene-edited baby experiments have raised serious ethical questions. Photo / 123RF

Concerns over the creation of a sub species of humans has led to a call from global scientists for a temporary ban on the use of powerful DNA editing tools to make genetically modified children.

The move is intended to send a clear message to rogue international scientists that experiments to rewrite the DNA of sperm, eggs or embryos destined for live births is unacceptable.

The demand for a global moratorium on the issue comes after last November's shocking announcement that gene-edited twins had been born in China in an experiment that was widely condemned by the scientific community.

Mainstream scientists generally oppose making babies with altered DNA, citing concern over tinkering with heritable genes. Such genetic changes may be passed to future generations, unlike gene editing done in parts of the body not involved in reproduction.

The need for a moratorium has been cited by 18 researchers from seven countries who published a commentary in the journal Nature.

"There has been growing interest in proposals for genetic enhancement of humans," the scientists noted. But the potential risks are too great without scientists agreeing to international standards or controls.

The idea is that a moratorium "will place major speed bumps in front of the most adventurous plans to re-engineer the human species".

Professor John Rasko from the University of Sydney School of Medicine supports the ban despite harbouring fears the horse has already bolted.

"The subtlety here is that we thought we'd already asked for a moratorium," he told ABC radio this morning.

"I've always been of the opinion that the future of the human race is through an international framework, through guidelines, through regulatory embrace."

Roughly 30 nations already prohibit making gene-edited babies, and the desire for a global "pause" on the science is largely aimed at China.

The country has drawn the ire of the scientific and medical community after Dr He Jiankui claimed he had altered human embryos with a powerful new tool resulting in the birth of genetically edited twin girls.

The incident is often referred to as the CRISPR baby scandal because of the scientific technique used in the experiment.

CRISPR is a recently emerged technology that can be thought of as acting like a tiny pair of molecular scissors that can cut and alter nucleotides that make up DNA, enabling scientists to find and modify or replace genetic defects.

It has the potential to help us fix diseases that have plagued humans for millennia. But if we get it wrong, we could do irreparable harm to all the generations to come.

There is a plausible concern that such a technique could accidentally introduce an error into the human gene pool, thereby inadvertently creating a new disease that could be passed on for generations.

The use of CRISPR has also set off a fierce debate about the ethical implications of potentially using the cutting-edge science to pick and choose the human condition.

Despite the lack of understanding about the precise heritability of intelligence, it is plausible that CRISPR could be used to enhance the intellect of unborn babies, not just their physical traits.

Among the proposals voiced by international researchers calling for a moratorium is for individual nations to pledge to block such research for a specific period, perhaps five years. Following that, each country could decide on its own about what to allow but only after taking steps like providing public notice, joining international discussions and determining whether its citizens support proceeding with such gene editing.

The proposal does not cover gene-editing experiments that don't involve trying to establish a pregnancy.