Mosaicism is a powerful biologic concept, originally developed from studying plants and animals. All cutaneous neoplasms, both benign and malignant, reflect mosaicism, which is the necessary basis to explain numerous human skin disorders. For example, various mosaic patterns visualize the embryonic development of human skin and X-linked skin disorders explain why women live longer than men, and so on. This book presents, for the first time, a comprehensive overview on the strikingly manifold patterns and peculiarities of mosaic skin disorders. This reader-friendly structured and straightforward publication will help the dermatologist to understand the underlying molecular mechanisms of skin disorders in order to further improve the treatment outcome.

This second edition offers a fully revised and updated work on a rapidly growing field of knowledge, and was prepared by two experts whose goal was to explain the molecular basis of mosaic skin disorders in a language that is accessible for practicing physicians and medical students alike. It presents a timely and comprehensive overview of the strikingly manifold patterns and peculiarities of mosaic skin disorders in a straightforward, reader-friendly way that will help physicians to further improve genetic counseling and treatment outcomes. The first two parts of the book are devoted to the mechanisms and patterns of cutaneous mosaicism, and include an explanation of genomic and epigenetic mosaicism and a description of the archetypical segmental patterns including the lines of Blaschko and the flag-like, phylloid and lateralization pattern, the non-segmental pattern of large congenital melanocytic nevi, and the sash-like arrangement as noted in a particular type of cutis tricolor. The concept of lethal mutations surviving as mosaics has now been confirmed by molecular analysis in many sporadically occurring phenotypes. The difference between monoallelic and biallelic traits has deepened our understanding of hereditary mosaics, especially of multiple benign skin tumors. Moreover, recognition of the fundamental difference between the simple segmental and the superimposed types of mosaicism is important for the purpose of genetic counseling. In the third part, the various mosaic skin disorders are examined in depth, including nevi, didymotic disorders, other binary genodermatoses, mosaic manifestations of autosomal skin disorders, and nevoid skin disorders such as phenotypes reflecting functional X-chromosome mosaicism or a superimposed mosaic manifestation of common skin diseases with a polygenic background. Reader-friendly and clearly structured, Mosaicism in Human Skin will appeal to both experienced dermatologists and residents in training, as well as to medical geneticists and pediatricians. .

Hair is the subject of this book, including the anatomy of the hair follicle, developmental stages, analyzed by light and electron microscopy, hair ultrastructure, nerve and blood supply, specialized hairs and hair organs, and a review of the present techniques to cultivate hair follicle cells in vitro. In the clinical part several chapters describe the most important diseases and possibilities for treatment. Hair care products and their toxicology are the subject of further sections. Extensive reviews of the antiandrogens, a most important group of drugs influencing hair growth, and of their clinical use in conditions such as androgenetic alopecias and hirsutism are included as well. Finally, surgical techniques for hair transplantation are discussed. This book is a standard textbook for everything pertaining to hair under normal and pathological conditions.

Hair is the subject of this book, including the anatomy of the hair follicle, developmental stages, analyzed by light and electron microscopy, hair ultrastructure, nerve and blood supply, specialized hairs and hair organs, and a review of the present techniques to cultivate hair follicle cells in vitro. In the clinical part several chapters describe the most important diseases and possibilities for treatment. Hair care products and their toxicology are the subject of further sections. Extensive reviews of the antiandrogens, a most important group of drugs influencing hair growth, and of their clinical use in conditions such as androgenetic alopecias and hirsutism are included as well. Finally, surgical techniques for hair transplantation are discussed. This book is a standard textbook for everything pertaining to hair under normal and pathological conditions.

Abstract: In 1945, the Journal of Heredity published an impressive article entitled "A human mosaic: bilaterally asymmetrical noevus pigmentosus pilosus et mollusciformis unilateralis." The author was M. Zlotnikoff, a Russian physician working in Ivanovo, a city located approximately 250 km northeast of Moscow. Zlotnikoff described a 24-year-old woman with a congenital linear epidermal naevus in a systematized and strictly unilateral arrangement. For the first time, the author explained this disorder as a mosaic resulting from a somatic mutation that occurred at an early stage of embryonic development. However, because this article was published immediately after the war, it fell into oblivion, despite the fact that it was of utmost importance in clinical dermatology. Zlotnikoff's work is all the more remarkable as the author had never heard of the lines of Blaschko

Abstract: Sarcoidosis is a chronic granulomatous disorder affecting the lungs, skin, and many other organs. Twin studies suggest that genetic factors account, to a large degree, for the etiology of the disorder. Hence, theoretically, we could postulate that the phenomenon of superimposed mosaicism in the form of a pronounced segmental involvement, overlaying the disseminated non-segmental lesions, should also occur in sarcoidosis. Indeed, one case suggesting superimposed mosaicism in cutaneous sarcoidosis was found in the literature and is reassessed here