While much of the world's attention is focused on the current COP21 climate change talks in Paris, another international summit is taking place this week that could have an equally vast impact on the future of the planet – and the human beings and animals that live on it.

Washington DC is playing host to a huge delegation of scientific experts from all around the world at the International Summit on Human Gene Editing, with today's rapid advancements in genetic science and gene-editing capabilities meaning there's a lot of ground to cover since the last meeting in the 1970s.

"There is a great deal to be gained through the use of gene-editing, but obviously we have to be careful how we proceed," one of the conference organisers, Robin Lovell-Badge, told Robin McKie of The Guardian. "The point of this meeting is to determine just how quickly we should move."

The lines are firmly divided on this extremely controversial and emotive topic. In one corner, advocates of gene-editing technology argue that it could help us eradicate diseases and inherited conditions that cause illness and misery all over the world.

In the other, researchers and ethicists warn that with gene-editing techniques like the CRISPR system, we are tampering with scientific forces that we don't yet fully understand.

"It would not be a good idea to impose a moratorium on this technique, since it is a really important and useful new technique with many possibilities for improving many aspects of medical practice such as cancer treatments," Shirley Hodgson, a geneticist from St George's University of London, told Sarah Knapton at The Telegraph. "A ban would either prevent important research in this area or drive it underground."

But such a ban is exactly what more than a hundred scientists and experts are calling for – at least with regards to human germline engineering, which would not only modify the genetic properties of one embryo but also all of that baby's descendants.

"Engineering the genes we pass on to our children and future generations would be highly risky, medically unnecessary, and socially fraught," said Marcy Darnovsky of the US Centre for Genetics and Society (CGS). "There is no good reason to risk a future of genetics haves and have-nots, a world with new forms of inequality, discrimination and conflict."

"Genetic modification of children was recently the stuff of science fiction," added Pete Shanks, a consulting researcher with the CGS. "But now, with new technology, the fantasy could become reality. Once the process begins, there will be no going back. This is a line we must not cross."

Just this week, researchers announced a new CRISPR editing method that makes cutting and pasting genetic code safer and more accurate than ever, and with similar advancements being made all the time, it will only become harder to reconcile the potential benefits of gene-editing techniques with the ethical and scientific dilemmas the technology poses.

"[T]he individuals whose lives are potentially affected by germline manipulation could extend many generations into the future," Francis Collins, director of the US National Institutes of Health, told The Guardian. "They can't give consent to having their genomes altered."