First edition. 2006 marks the 50th anniversary of the discovery of the human chromosome number, a finding that initiated human cytogenetics as a scientific discipline and set the basis for much of modern medical genetics. First Years of Human Chromosomes draws together the ground-breaking work of the main researchers in the key period 1955 to 1960. The book is based on interviews with these researchers and descriptions of their major findings, giving a strong sense of the excitement and thoughts of those involved at the time. To complete the picture, it also features a CD containing extracts from the interviews themselves. First Years of Human Chromosomes provides a unique record of this crucial period of scientific research and medical advance, and will appeal to all those working in the field of genetics, whether scientists or clinicians.