William McGinnis, ’78 Biology, has always wondered how the world works. How have animals evolved and what traits do we all share?
Intrigued by Nobel prize winner Ed Lewis’ research, McGinnis became fascinated with embryonic development as an undergraduate at San Jose State. Because animals appear in many shapes, scientists assumed they had different genes. McGinnis explored hox genes, which help animals develop diverse shapes. His work with fruit flies led to an important discovery: the same hox genes present in fruit flies exist in most animals, which implies a connection to Earth’s earliest organisms. By understanding the genes that unite us all, McGinnis says, we can better study how cells diversify, adapt and thrive.
“The hox gene discovery was surprising because it was thought that because animals develop different structures, they couldn’t possibly have the same genes controlling development,” says McGinnis, a cell and developmental biology professor at UC San Diego. His research showed that hox genes have the same function in all animals—to tell different regions of the body to develop diverse shapes. “I was fascinated by how a single, fertilized egg can become the enormous diversity of animal forms that we see throughout nature—worms, snakes, crustaceans, insects, humans, elephants, etc. The same set of genes are redeployed to control morphology, the shape of animals.”
In 2019, McGinnis earned membership into the National Academy of Sciences, an honor recognizing his body of work. He continues to explore how cells develop, always with the purpose of understanding what differentiates us and why.
“Evolution is an adaptation to new conditions,” he says. “As conditions on Earth change, animals and plants evolve to adapt. We don’t know the future, but the process of science is a slow one that reveals novel truths that steadily improve the living conditions of billions of people.”