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CRISPR: Rewriting the Code of Life

Technology · 4 min read

CRISPR-Cas9 has revolutionized genetic engineering, making precise DNA editing faster, cheaper, and more accessible than ever before. This technology, adapted from bacterial immune systems, allows scientists to target and modify specific genes with remarkable accuracy.

Bacteria use CRISPR systems to remember and destroy viruses. Scientists Jennifer Doudna and Emmanuelle Charpentier realized this system could be reprogrammed to cut any DNA sequence, earning them the 2020 Nobel Prize in Chemistry.

The process is elegantly simple. A guide RNA directs the Cas9 protein to a specific DNA location. Cas9 cuts both strands. The cell's repair mechanisms then either disable the gene or incorporate a provided template—allowing deletion, correction, or insertion of genetic material.

The He Jiankui Scandal

In 2018, Chinese scientist He Jiankui announced he had created the first gene-edited babies—twins with a modification intended to confer HIV resistance. The scientific community condemned his work as premature and ethically unjustifiable. He was imprisoned for illegal medical practice, but his actions forced urgent discussions about editing human embryos.