We all have stripes on our body from birth, even if we can’t see them. Stripes that form spirals on our heads, cross the face and reach our extremities and on the back where they form a “V”. They are totally invisible to the human eye. Alfred Blaschko discovered them while studying, in the 19th century, skin eruptions, moles and birthmarks. For this reason they are called Blaschko’s lines.
The Blaschko lines were discovered in 1901.
Blaschko presented his study in 1901 at the Congress of the German Dermatological Society. In it he shared that he detected many lines in the skin that follow similar patterns, as if they were paths to travel along the human body.
At that time, surgeons recognized Langer’s lines. These lines are the ones they follow to make an incision when performing a surgical operation. They mark the areas of the body where there is less skin tension, so they have better healing. Langer’s lines are parallel to the nature of the collagen fibers in the dermis and perpendicular to the muscle fibers.
Baschko collected data from his patients who had skin conditions and mapped the distribution of these lesions. Although he died in 1922, his study of these lines set a precedent for future research.
Map of Blaschko’s lines
After a century, researchers at the University of Marburg in Germany followed in his footsteps. Rather, they added lines to the original map of our body that Baschko had drawn.
To produce this mapping, they studied 186 cases of people with skin lesions on the head and neck. On the face, Baschko’s lines are distributed like an hourglass, with the thinnest part at the nose. In other areas, the lines are configured with 90° angles, while under the scalp they form a spiral.
The scientists’ conclusion is that these lines have been present since man developed. In the remote beginning, we were a single cell. As the cells reproduced and multiplied, our body took its present form. During this development, each cell is pushed by another and thus, they are swirling and moving.
The invisible lines that mark this path during the period of development are the Baschko lines. They are formed by the path of melanocytes and pigmentation-causing cells located deep in the epidermis. In turn, inheritance from our parents also influences their formation.