Hermann Werner Siemens

Overview
Hermann Werner Siemens (20 August 1891, Charlottenburg -21 December 1969, Leiden ) was a German dermatologist who first described many skin diseases and was one of the inventors of the twin study.

Biography
He studied at Berlin and Munich universities, receiving his doctorate in 1918. In 1929 he became chair of dermatology at Leiden University in the Netherlands.

Siemens published "Zwillingspathologie" (Twin Pathology) in 1924 which introduced the widely used "classical twin method". He was the first to use both identical and unidentical twins in a single study (to determine the role of genes over environment in skin moles). His influence on the invention of the twin study is not widely acknowledged, possibly due to his support during the Second World War of the Nazi party's eugenics program. . However, in 1942 he had lost his chair at Leiden and was temporarily held hostage due to his resistance to the German occupation policies, and after the war he regained his position, which he held until 1962.

Diseases named after H.W.Siemens:


 * Christ-Siemens-Touraine syndrome (Hypohidrotic ectodermal dysplasia)
 * Hallopeau-Siemens syndrome (Recessive dystrophic epidermolysis bullosa)
 * Ichthyosis bullosa of Siemens
 * Siemens' syndrome 1 (Keratosis follicularis spinulosa decalvans)
 * Bloch Siemens syndrome (Incontinentia pigmenti)