On Aug. 26, 2025, scientists at Georgia State University (GSU) announced a study published in Scientific Reports that used CRISPR gene editing to bring back a gene that humans lost millions of years ago — and in the process, lowered uric acid levels that cause gout and other conditions.

Gout, a form of arthritis caused by crystals that build up in joints and cause swelling and pain, is one of humanity’s oldest diseases. The missing piece is uricase, an enzyme most animals still have. Uricase breaks down uric acid, the waste product that builds up in blood. When levels climb too high, uric acid forms crystals in the joints and kidneys, leading to painful gout, kidney disease and other health problems.

Humans and other apes lost the uricase gene roughly 20 to 29 million years ago. Some scientists suggest this wasn’t entirely bad at the time. Researchers such as Dr. Richard Johnson at the University of Colorado have proposed that higher uric acid levels helped early primates turn fruit sugar into fat, a survival advantage during food shortages, according to a study in Seminars in Nephrology.

Still, what once helped our ancestors survive now contributes to modern diseases, and that’s what Eric Gaucher, a biology professor at Georgia State, and his team set out to challenge. “Without uricase, humans are left vulnerable,” said Gaucher, the study’s co-author. “We wanted to see what would happen if we reactivated the broken gene.”

The results were dramatic: Uric acid dropped and fructose-driven fat buildup in liver cells was prevented. But results in isolated cells aren’t always enough, so the team pushed the experiment further.

To see if the gene would behave the same way in more complex conditions, the team moved from simple liver cells to 3D liver spheroids. These miniature lab-grown tissues mimic how organs work in the body. The revived uricase gene lowered uric acid there, too. The enzyme also found its way to peroxisomes — tiny compartments inside cells where uricase normally does its job. That finding suggests the therapy could function safely in living systems, not just in isolated cells.

Next come animal studies and, if results hold, human trials. Potential delivery options range from direct injections to returning lab-modified liver cells to patients. Another option is lipid nanoparticles — the same technology used in some COVID-19 vaccines.