The team, led by cancer geneticist Keith Cheng, M.D., Ph.D., a Jake Gittlen Cancer Research Foundation researcher in the Penn State Cancer Institute, at Penn State College of Medicine, Penn State Milton S. Hershey Medical Center, in collaboration with University Park anthropologist Mark Shriver, Ph.D., found that a change in just one amino acid in one gene plays a major role in determining why people of European descent have lighter skin than people of African descent.
The find could lead to further research using the protein coded by the pigmentation gene as a target for treatment of malignant melanoma, the most deadly form of skin cancer, as well as to research on ways to modify skin color without damaging it by tanning or using harsh chemical lighteners.
The findings will be published as the cover story in the December 16 edition of Science magazine.
The genetic determination of human skin color is one of biology's enduring mysteries.
Previous studies on pigmentation have identified more than 100 genes involved in pigment production. Alterations in some of these genes are associated with disorders such as albinism, which causes very light skin, but also vision problems. However, most of the genes responsible for normal differences in skin pigmentation remained unknown. The gene identified by Cheng's team called SLC24A5 previously had not been suspected to be involved in pigmentation.
The pigmentation discovery was an unexpected offshoot of cancer research Cheng began a decade ago using zebrafish, a common aquarium pet that is widely used as a model organism for studying the genetics of development. The zebrafish reproduces rapidly, and many of its genes are similar to humans, which makes it a go
Contact: Megan Wald Manlove