Whenever there’s progress in the field of genetics, there’s cause for worry. For some years now, these mixed feelings are being evoked by a gene-altering technology called CRISPR (clustered regularly interspaced short palindromic repeats), which refers to a suite of gene-editing techniques. It can be used to target specific stretches of genetic code and to edit DNA at precise locations, permanently modify genes in living cells and organisms, and possibly correct disease-causing mutations. So far, all of the CRISPR-related research is focussed on plants, animals and lifeforms far removed from the human universe. Last week, a team from China reported intriguing results from CRISPR-modified human embryos.
According to the New Scientist , the team has corrected genetic mutations in a few cells in three normal human embryos using CRISPR. Previous attempts have always been on abnormal human embryos and success rates (typically less than 10%) were too low to be viable. In this study, normal embryos, tweaked by deleterious mutations introduced by genetically diseased sperm, were corrected. The numbers involved are still low, but the fact that normal embryos seemed to be more receptive to gene-editing is a queasily exciting development.
Improving the human stock
Historians of genetic engineering technology, most recently Siddhartha Mukherjee, have warned that societies, nations and other human collectives have been obsessed with improving the human stock. While it might appear that we’ve cured ourselves of our eugenic baggage, science soldiers on to find genes for disease, and the modern personalised genetic test, now also available to the Indian affluent, hopes to warn Indians of possible genetic disorders in their unborn. Notions of ‘disease’ keep changing and while a warning about the fatal familial insomnia (that causes you to die of sleeplessness) may make a decision to abort easier, would a genetic basis for autism or early coronary heart disease make it morally compelling for a couple to terminate a foetus? Beyond ridding the body of known disease, would CRISPR-led tweaks to, say, increasing expression of certain genes that improve athletic endurance be acceptable, a kind of womb-level doping?
Another complication is that CRISPR-led attempts to correct certain genes can sometimes lead to nearby, off-target genes also getting altered (mosaicism). In the quest to correct aberrations, would it be worth the risk to fix what isn’t broken? The Committee on Human Genome Editing said in a report last month that gene-editing techniques were too risky to be made widely available. While scientists and ethicists may have so far made the right political noises about restraining gene-editing technology, bruising patent battles are already under way over intellectual property rights to the CRISPR technology. That means commercial interest in it is already so high that there is enough incentive for commercial interests to organise lobbying efforts and bring in legislation to offer gene-editing as a product. CRISPR, yet, can’t excise the Orwellian.