Coral in Your Bones

| by Ocean Wise

In the 1960s, Dr. Eugene White was diving amongst the corals of the South Pacific when he noticed something curious. As a professor of material sciences at Pennsylvania State University, his eye was trained to look at the structure of things and the porous reef looked an awful lot like the spongy marrow of bone.

Intrigued, Dr. White and his nephew, Rodney White, a medical student, began to explore whether coral could actually replace human bone. At the time, the medical community was eager to improve invasive bone-grafting surgeries. 

Hips, ribs and skulls were often harvested from the patient, or from cadavers, to plug a hole elsewhere in the skeleton. This two-step surgery boosted the chance of scarring and infection. The Whites, along with a team of researchers, soon discovered that human bone would indeed fuse with coral’s porous structure. 

“From coral jaw bones to sea-sponge cancer drugs, the reef ecosystem is becoming a force in the medical field”

One reason that coral can replace bone is that coral is a kind of bone. The electric-coloured stony reefs are actually hundreds upon thousands of exoskeletons stuck together

Built by tiny stationary animals called polyps that live together in massive colonies, these creatures have developed top-notch defence skills against predators. They can retract into their exoskeleton for safety, but mostly they spend their time waving their miniature harpoon-tipped tentacles around trying to skewer food. 

When a polyp gets too big for its britches, it lifts itself up and out of the exoskeleton and starts building a new one. When they move up, they leave a little gap underneath their new home. This happens again and again, creating perfectly interconnected tunnels that make coral an ideal bone replacement.  

Photo: jayhem

After a coral-bone graft, human cells move into the former homes of polyps and make them their own. Eventually, the tissue fully replaces the coral, leaving healed bone in its place.  

In 2012, the Whites’ discovery won a Golden Goose Award for obscure research leading to a scientific breakthrough. Coralline-ceramic surgery is now mainstream, with hundreds of thousands of patients walking around with coral-based bone grafts.  

But researchers are still perfecting the procedure. By seeding lab-grown coral with stem cells and enriching it with minerals that spur bone growth, scientists observed that coralline grafts are healing faster than those that use the patient’s own bone.  

From coral jaw bones to sea-sponge cancer drugs, the reef ecosystem is becoming a force in the medical field. So many reef-derived drugs are under review that the ecosystem has rightfully earned the moniker “the medicine cabinet for the 21st century.”  What other miracle potions are waiting in the coral reef for someone like Dr. White to swim along and spot the potential?