Every spring, male deer undertake a unique biological ritual: sprouting and rapidly regrowing their massive, spiky antlers.
A complex matrix of bone, living tissue and nerve endings, deer antlers can reach 50 inches long and weigh more than 20 pounds before they are shed in winter. Not only are the antlers useful in attracting mates and fighting, they qualify deer as the only mammal that can regrow lost body parts.
Now, researchers say they have identified the two genes primarily responsible for antler regeneration in one species, red deer. The study, reported Tuesday in the Journal of Stem Cell Research and Therapy, notes that these genes are also found in humans, potentially opening new avenues of research into bone trauma and diseases.
“Deer antler formation shares similar biological mechanisms with human bone growth, but deer antlers grow much faster,” said Peter Yang, an orthopedic researcher at the Stanford University School of Medicine and senior author of the study. Perhaps by studying the newly identified genes in humans, scientists may be able to developed treatments that could “reproduce the rapid bone growth of deer antlers in human bone,” and provide relief for people who suffer ailments like osteoporosis.
Dr. Yang first took an interest in antlers during a 2009 vacation to Alaska’s Denali National Park, where a tour guide noted that the deer can grow their bony appendages nearly an inch each a day in summer. “Since then, I’ve been fascinated by them,” he said.
He and his colleagues traveled to a deer farm in California to take samples of early antler tissue — which consists primarily of stem cells — from male red deer. After analyzing the genes in the samples, the researchers tried shutting down some and “revving up” others to determine which function they controlled. They compared samples of RNA — molecules that deliver messages in genes — from the antlers with human RNA in search of overlaps. They then tinkered with the relevant genes in mice to see how they affected tissue growth.
The team eventually narrowed their focus to two genes, uhrf1 and s100a10, both of which have previously been linked to bone development in humans. They found that when the uhrf1 gene was shut down, the rate of bone growth in the mice significantly slowed. And when the s100a10 gene was put into overdrive, calcium deposits increased and the engineered cells mineralized more rapidly.
Dr. Yang and his team concluded that uhrf1 and s100a10 work in tandem to generate rapid antler growth in deer: uhrf1 promotes tissue generation, and s100a10 supports the hardening, or mineralization, of that tissue.
If true, the findings may have some “really interesting applications for human health,” said Dr. Yang.
Though the regeneration of body parts is more often associated with salamanders and spiders, researchers have speculated that humans, with a little genetic prodding, should also be able to regrow lost tissue. Even salamanders contain no special gene for regeneration, and humans already have the ability to grow new skin and sections of lost ribs.
Human application of Dr. Yang’s findings are a long ways off, and the findings must be confirmed in other deer species. But he hopes the new research will lay a foundation for future studies.