Monstrous births and inborn handicaps were known from the antiquity onwards, but dysmorphology—the study of inborn anomalies—came into being in the twentieth century. In the early twentieth century, pediatricians started to collect data on hereditary diseases and non-hereditary neonatal malformations. In the 1920s and 30s, many such malformations were attributed to a presumed hormonal imbalance. The development, in 1956, of an efficient method to stain and count human chromosomes led to redefinition (c. 1960) of some of the most frequent inborn anomalies (Down syndrome, Turner syndrome) as aneuploidies—that is, an abnormal number of chromosomes. This observation favored research on these conditions. In the 1960s, interest in fetal anomalies was further stimulated by the Thalidomide disaster—the production of major fetal malformations by a new drug, and a worldwide epidemic of rubella (German Measles) that led to a sharp increase in number of malformed fetuses. The latter two events led to the establishment of national and international registries of neonatal malformations. Accumulation of data on this topic favored in turn the rise of dysmorphology as a distinct branch of knowledge. In the 1960s, physicians interested in dysmorphology investigated mainly environmental factors: (pollution, radioactivity), infectious diseases (rubella, toxoplasmosis, herpes simplex, varicella), and effects of drugs adsorbed during pregnancy. In the late twentieth century the focus had shifted to studies of hereditary conditions, and attempts to uncover the genes responsible for these conditions.
The aim of this research was to follow the history of dysmorphology and its transformations from the 1920s until today, in order to study how classifications and collections defined the boundary between the normal and the pathological, stabilized specific syndromes and destabilized others, homogenized diagnoses and interventions, and promoted the "geneticization" of research on inborn deformities. A particular focus was on the history of four databases: the London Dysmorphology Database (the Winter-Baraitser Dysmorphology Database and photo library), the Paris-based Orphanet network of rare diseases, the Ulster-based Eurocat (European surveillance of congenital anomalies), and the Rio de Janeiro-based ECLMAC (the Latin American Collaborative Study of Congenital Malformations).