Skin & Hair Pigmentation

The main determining factor of skin and hair color is their content and type of the pigment Melanin, which is synthesized by melanosomes - organelle uniquely made in skin cells called melanocytes. There are two main types of melanin (brown-black eumelanin and red-yellow pheomelanin) and the relative amounts of each determine your skin and hair color. 

Here in the Charles Institute we study the regulated sequence of cell biologic and molecular biologic events that regulate skin/hair pigmentation in both healthy and pathologic states (e.g., vitiligo, canities, melasma).

Skin Pigmentation (Tobin Lab)

Skin pigment levels are closely linked with our geographic ancestral origins, as can be seen by higher pigment levels in the skin of humans originating in regions of lower latitude with higher ultraviolet radiation (UVR) levels.

Of all our phenotypic traits skin and hair color communicate more immediate information to the observer than any other. Humans display a rich and varied palette of surface color that not only highlight striking superficial variations between human sub-groups, but also underscore how we differ phenotypically from other mammalian species. Skin and hair colors are derived from the pigment melanin, synthesized via an ancient biochemical process termed melanogenesis. Synthesis occurs within melanosomes - specialized organelles unique cells called melanocytes. Current diversity of human skin color is regulated at both intrinsic and extrinsic melanogenesis levels. The former refers to the individual's genetically determined level, as well as type, of synthesized melanin. The latter refers to how their skin responds to stimulation of additional pigmentation from intrinsic (e.g., secreted melanogens) or extrinsic (e.g., UVR) sources.

Our research here in the Charles Institute of Dermatology is focused on multiple basic, applied and translational aspects of skin and hair pigmentation at the cellular and molecular levels from both healthy and disease states including melanoma; an often-fatal cancer of the melanocyte.