Biotechnology advances expand genetic code and enable light-based reprogramming

Researchers at the University of California San Diego have successfully expanded the natural genetic alphabet. While life on Earth has traditionally relied on four chemical bases—Adenine, Thymine, Cytosine, and Guanine—scientists have introduced two new synthetic pairs, known as the ‘Hachimoji’ system. This expansion allows the cellular machinery, specifically the RNA polymerase enzyme, to read and copy an eight-letter genetic code without error.

Parallel advancements in synthetic biology are exploring ways to reprogram genetic code using light. Led by neurotechnologist Matthew Pava through DARPA, new research aims to combine optogenetics with synthetic biology. This method involves encoding genetic sequences into light patterns and irradiating genetically modified cells, instructing internal tools to assemble specific RNA or DNA strands.

These breakthroughs could significantly impact personalized medicine, agriculture, biofabrication, and space exploration. However, experts note potential risks, including the accidental or intentional production of toxins and the possibility of modified cells escaping biological control.