Free levelled English reading practice. Read for meaning first, then use the full Speed Reading tool to time yourself and track your progress.
CRISPR gene editing adapts a bacterial defence mechanism into a programmable molecular tool. In a common system, guide RNA directs the Cas9 enzyme toward a selected DNA sequence, where Cas9 makes a cut. Cellular repair can then disrupt a gene or facilitate a designed change. The method’s relative simplicity and flexibility accelerated research and enabled new therapies, including treatments for sickle cell disease. Yet ethical distinctions matter. Editing somatic cells in a patient affects that individual, whereas changes to embryos or reproductive cells could become heritable. The 2018 announcement of gene-edited babies in China provoked international condemnation because the intervention lacked compelling medical justification and exposed future children to uncertain risks. CRISPR thus demonstrates how scientific capacity can advance faster than institutions develop legitimate rules for its use.
