Café-au-lait spots in McCune-Albright syndrome

(A) A typical lesion on the face, chest, and arm of a five-year-old female with McCune-Albright syndrome, which demonstrates jagged "coast of Maine" borders and the tendency for the lesions to both respect the midline and follow the developmental lines of Blaschko (a configuration of skin lesions characterized by arcs on the upper chest, S shapes on the abdomen, and V shapes over the posterior midline, caused by patterns of X-chromosome inactivation).