Study Identifies Genes Responsible for Diversity of Human Skin Colors

Human populations feature a broad palette of skin tones. But until now, few genes have been shown to contribute to normal variation in skin color, and these had primarily been discovered through studies of European populations. Now, a study of diverse African groups has identified new genetic variants associated with skin pigmentation. The findings help explain the vast range of skin color on the African continent, shed light on human evolution and inform an understanding of the genetic risk factors for conditions such as skin cancer.

“We have identified new genetic variants that contribute to the genetic basis of one of the most strikingly variable traits in modern humans,” says Sarah Tishkoff, a Penn Integrates Knowledge Professor and the David and Lyn Silfen University Professor with appointments in both the School of Arts and Sciences and the Perelman School of Medicine. “When people think of skin color in Africa most would think of darker skin, but we show that within Africa there is a huge amount of variation, ranging from skin as light as some Asians to the darkest skin on a global level and everything in between. We identify genetic variants affecting these traits and show that mutations influencing light and dark skin have been around for a long time, since before the origin of modern humans.”

The findings are published in the journal Science. Tishkoff, senior author, collaborated with first author and lab member Nicholas Crawford, a postdoctoral fellow, and a multi-institutional, international team.

Tishkoff has long studied the genetics of African populations, looking at traits such as height, lactose tolerance, bitter-taste sensitivity and high-altitude adaptation. Skin color emerged as a trait of interest from her experience working on the continent and seeing the diversity present across groups.

Click here to read the full story.

Arts & Sciences News

Azuma and Hart Named Roy F. and Jeannette P. Nichols Professors of American History

Eiichiro Azuma specializes in Asian American and transpacific history, while Emma Hart teaches and researches the history of early North America, the Atlantic World, and early modern Britain between 1500 and 1800.

View Article >
Arts & Sciences Students Honored during 37th Annual Women of Color Day

Sade Taiwo, C’25, and Kyndall Nicholas, a Ph.D. candidate in neuroscience, were honored for their work.

View Article >
Nine College Students and Alums Named Thouron Scholars; Will Pursue Graduate Studies in the U.K.

The Scholars are six seniors and three recent graduates whose majors range from neuroscience to communication.

View Article >
Irma Elo Named Tamsen and Michael Brown Presidential Professor in Sociology

Elo’s main research interests center on inequalities in health and mortality across the life course and demographic estimation of mortality. In recent years, she has extended her research to include predictors of cognition in high-, middle-, and low-income countries.

View Article >
Julia Hartmann Named Fay R. and Eugene L. Langberg Professor in Mathematics

She specializes in algebra and arithmetic geometry, a newer field that applies techniques from algebraic geometry to solve problems in number theory and co-developed the method of field patching.

View Article >
Holger Sieg Named Baird Term Professor of Economics

Sieg focuses his research on public and urban economics, as well as the political economy of state and local governments.

View Article >