Perelman School of Medicine

Congenital heart valve defects appear in 2 percent of all live births, making them the most common type of birth defect. While some of these defects have been linked to specific genetic mutations, the majority have no clearly definable genetic cause, suggesting that epigenetic factors – changes in gene expression versus an alteration in the genetic code -- play an important role.

James C.

Notch is one of the most frequently mutated genes in chronic lymphocytic leukemia (CLL), the most common leukemia in adults in the United States. It is also often mutated in other common B cell tumors, such as mantle cell lymphoma. However, the role of Notch in these cancers has been uncertain.

Imagine trying to take a picture of a runner, but only being able to see her feet. If you could see her whole body, you’d get the full picture of how she uses both legs to put one foot in front of the other to reach top speed.

Autoimmune diseases tend to strike women more than men and having multiple X chromosomes could be the main reason why. While a process called X chromosome inactivation serves to balance out gene dosage between males and females, some genes on the “inactive X” chromosome in immune cells can sometimes escape this process, giving women an extra dose of immunity-related gene expression.

Seven University of Pennsylvania faculty members have been elected to the National Academy of Medicine (NAM), one of the nation’s highest honors in biomedicine. They are among 70 new U.S. and 10 international members of the globally renowned organization.

Have you ever been stuck in a rut, going through the same motions day in and day out? How do you motivate to change your behavior?

Noroviruses are the leading cause of non-bacterial gastroenteritis in the world and are estimated to cause 267 million infections and 20,000 deaths each year. This virus causes severe diarrhea, nausea, and stomach pain.

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.

As Hurricane Maria formed in the Atlantic, then turned into a powerful storm barreling toward Puerto Rico, Arjun Yodh watched the news closely.