Gene genies

By starting to rewrite mankind’s genetic code, scientists in London’s King’s Cross are working at the frontier of technolog y and morality – and potentially changing our species forever. Welcome to the brave new world of genomics. By Harry de Quetteville.

How advances in genetic engineering could change the human race for ever. By Harry de Quetteville

How many cells are there in your body? no one knows for sure. The best guess is about 37 trillion. and all of them ( bar r ing red blood cells, a nd tough cells in your hair a nd nails) have a nucleus containing your entire genetic code – or genome.

your genome governs what your body looks like and, in many ways, how it responds to its environment. embedded within it are the instructions whose combinations, variations or corruptions influence, among myriad other things, the colour of your eyes, your behaviour and your susceptibility to disease. Unravelled, it would be taller than you – about two metres. Put it under the microscope and you’ll see the three billion Dna molecule pairs that form it, clumped together in 20,000 or so genes arrayed among 46 chromosomes. your genome is an astonishing, dazzling compendium of information – a microscopic book of life, in which chromosomes, genes and Dna are the chapters, paragraphs and words.

now, though, researchers around the world, from china and america to sweden, are seeking to rewrite that book. and Britain is at the front of the pack.

since 2012, a technique known as crispr-cas9 has made the process of finding a specific location in a genome’s long thread,

cutting it, and guiding in new genetic information simple and cheap. With it, a door has opened to a world of bespoke genetic modification, as well as intense et hical, philosophical and medical debate. For Crispr-cas9 has the potential to modify not just an individual’s genome, but also – in what is known as germ-line editing – the genetic information they pass down to their children. As a result, it has the potential irreversibly to alter the genetic recipe of our species – not just to offer cures for devastating maladies such as HIV and cancer, but permanently, say, to wipe crippling heritable diseases from the slate of human affliction.

Yet precisely because genome modif icat ion possesses almost limitless power to change us, it is also freighted with unknowable ramifications for humankind. Such are the concerns among the world’s leading scientists that in December 2015 a meeting was convened by the US National Academies of Sciences and Medicine, the Chinese Academy of Sciences and Britain’s Royal Society. The organisers noted that it would be ‘irresponsible to proceed with any clinical use of germ-line editing’ without wider popular acceptance and greater safety measures. As things stand, there are still no agreed international laws governing the radical gene-editing techniques