This volume consists of the symposia presented at the Fourth International Congress of Human Genetics that was held in Paris in September 1971. It consists of 52 individual contributions, arranged in 11 different symposia or chapters. Eight of the papers are in French, all the others in English. The authors are, without exception, highly respected human geneticists, and the list of authors reads like a Who's Who in Human Genetics.
The field of human genetics has, in the last years, experienced an explosive growth. Previously, the literature of human genetics consisted mainly of descriptions of pedigrees, twin studies, rather superficial chromosome studies, and similar preliminary work. Geneticists, in general, believed that man, because of his long generation time, his small family size, and his complex morphology and physiology, was an inconvenient object for genetic studies. Lately, it has turned out, however, that man is actually a very favorable object, because