research describing a 24-year-old woman with a unilateral, systematized nevus across the left side of her body, and proposed that the disorder was due to a mutation during the cell cleavage stage of development. Based on this hypothesis, Zlotnikov suggested that the only probable explanation for the sagittal asymmetry of the disease was a genetic mosaicism in the patient. However, this proposal was not widely explored until re-hypothesized by German dermatologist Rudolf Happle in the 1970s due to the state of genetic and medical research in the Soviet Union at the time, and recent end of World War II. The lines of Blaschko were first referred to as such by the English-speaking medical community after 1976, when Robert Jackson published a review and reconsideration of Blaschko's research. Jackson wished to inspire interaction between dermatologists who saw Blaschko's lines in patients, and developmental biologists studying embryology and chromosomal abnormalities such as mosaicism. Scientists such as Rudolf Happle and Jean Bolognia have further differentiated Blaschko's lines from other linear phenomena such as Langer's lines and expanded the map of the lines over the human body to include areas of the head, face, and neck, where Blaschko's original maps did not cover. In 1985, Rudolf Happle proposed a link to lyonization and investigated the link to other X-linked skin disorders. Since that year, Scientists have continually explored the developmental hypothesis for the origins of Blaschko's lines, having found biological evidence to support the theory and linking the lines to other mosaicism and genetic-development related conditions and phenomena of the skin. See also Head zones (dermatomes) Kraissl's lines Langer's lines List of cutaneous conditions References External links Description of Blaschko's lines Picture of the Blaschko's lines Illustrations of the various patterns of cutaneous mosaicism Understanding Genetics - ask a geneticist Skin anatomy Skin lines