<unk> , also called the<unk>  of<unk> , named after German dermatologist Alfred<unk> , are<unk>  of normal cell development in the skin. These<unk>  are invisible under normal conditions. They become apparent when some diseases of the skin or mucosa manifest themselves according to these patterns. They follow a V shape over the back, S-shaped whirls over the chest and sides, and wavy shapes on the head. The<unk>  are believed to trace the migration of embryonic cells. The stripes are a type of genetic mosaicism. They do not correspond to nervous, muscular, or lymphatic systems. The<unk>  can be observed in other animals such as cats and dogs. Alfred<unk>  is credited with the first demonstration of these<unk>  in 1901.
Blaschko's lines
Gilula's lines
Beau's lines
Langer's lines
Pastia's lines
Curschmann's spirals
Perkin's line
Hampton's line