Should We Just Control Pests, Or Wipe Them Out Completely?
But if only one chromosome is edited, the moths can still live long enough to reproduce.
By inserting genes for all three CRISPR tools into the moth’s DNA, scientists might eventually be able to make the fatal mutation spread, eliminating the species. Chinese scientists use CRISPR to destroy the Wnt1 gene in Dendrolimus punctatus, a moth which causes particular harm in Asia, where it defoliates trees. After both gene chromosomes have been edited, the newborn caterpillars don't develop or grow properly, and soon die.
like to cut in two. The is done with an enzyme called Cas9. After cutting, the cell automatically repairs the damage using a DNA template. By carefully designing such a template, scientists are able to actually edit the cell's DNA, permanently.
Because the three tools are easy to make, CRISPR is much cheaper than older gene editors. But it's also more accurate, and the risk of accidental gene alteration is minimal. Which makes it safe to use on humans... at least in theory, it's not quite ready for your GP year!
And best of all, CRISPR edits can be carried out in one step, so experiments that used to take years now take mere days.
NEW IMMUNE SYSTEM KILLS CANCER
Armed with CRISPR, scientists now engage in the combat against genetic diseases, which have so far been impossible to cure. CRISPR has already indicated a glimpse of the solution. Scientists from the US injected the CRISPR tools into the muscles of mice, which suffered from muscular atrophy, and the gene editor partly repaired the sick gene, so the mice regained some of their muscular strength.
However, scientists’ top priority is a cure for cancer - or rather, a way of editing cancer out of a patient's DNA profile.
That's why cancer is the focus for the first CRISPR trials on humans, in the US and China. Scientists will extract some of the
patient’s immune cells to alter the genes, so the cells become able to track down and kill the cancer cells. The first results of the ground-breaking experiments will probably be published in a year from now. In the meantime, scientists will make new progress that will have even larger consequences for life on Earth.
GENETICISTS DESIGN NEW SPECIES
CRISPR allows scientists to play with millions of years of evolution, and in a few years, it could change life on Earth for good. With focused gene change, scientists can design brand new plant and animal species with desirable characteristics.
Genes which code for the CRISPR tools can also be inserted into disease-carrying insects such as malaria mosquitoes, making fatal mutations spread among the mosquitoes, so the species will be wiped out.
But the method could also bring back extinct species by recreating their genes in modern relatives’ DNA. In 2015, scientists inserted mammoth genes into elephants, and they plan to turn back bird evolution to the era of the dinosaurs.
CRISPR is also about to affect human evolution. Chinese scientists have used the method to correct gene defects in human embryos and introduce gene change to cause HIV virus resistance. Only ethical concerns prevent scientists from designing kids with genes that will give them larger muscles or stop ageing, so CRISPR could turn the next generation into superhumans.