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Gene Editing

RNA editing start-up Amber Bio launches with $26 million

Amber Bio aims to develop therapies that can make kilobase edits at a time

by Shi En Kim
August 4, 2023


Amber's cofounders, Jacob Borrajo on the left and Basem Al-Shayeb on the right. Both people are sitting on the steps in a stairwell.
Credit: Amber Bio
Amber's cofounders, CEO Jacob Borrajo (left) and chief technological officer Basem Al-Shayeb (right).

Amber Bio has launched with seed funding of $26 million. The San Francisco-based biotech is developing an RNA-editing platform that can rewrite thousands of bases on a single strand in one fell swoop.

According to the firm’s scientific founders, this mass gene editing technique is more scalable than creating a drug for every disease-causing mutation. “Having to create a single drug for every one of those mutations would go through a lot of [research and development], manufacturing, or regulatory hurdles,” says Basem Al-Shayeb, cofounder and chief technological officer of the company. Unlike the existing paradigm for gene correction, Amber’s technology promises to address multiple mutations in one go.

If the genome is a book, other gene-editing technologies work like a pencil or an eraser, altering just a few letters at a time. By contrast, Amber’s approach can make much larger edits. “We’re really changing pages at a time here,” says Jacob Borrajo, Amber’s other cofounder and CEO.

To make these much bigger RNA edits, Amber has engineered new Cas-protein-based systems and guide RNAs.

Moreover, editing RNA strands instead of DNA potentially makes Amber’s medicines safer. If DNA editing introduces errors, these mistakes in the genome are permanent. Editing RNA strands dodges such hazards, since the RNA will eventually degrade in the body.

For starters, the company is exploring the application of its technology to tackling ophthalmology and central nervous system diseases.

Both Al-Shayeb and Borrajo are each the alumnus of the two rival institutes for gene editing: Al-Shayeb is the academic descendant of Nobel-Prize-winning biochemist, Jennifer A. Doudna, at the University of California, Berkeley; whereas Borrajo graduated from the Broad Institute of the Massachusetts Institute of Technology and Harvard University. “It’s certainly a very unconventional . . . to have a scientist from Berkeley and one from MIT and Broad to be developing and learning together,” Al-Shayeb says of his partnership with Borrajo. “But at the end of the day, [Berkeley and Broad] are the two leading research institutes in this space. And we both have a common goal and vision.”



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