Teratology – past, present and future

Abstract

Teratology is the science that studies the causes, mechanisms, and patterns of abnormal development. The authors present an updated overview of the most important milestones and stages of the development of modern teratology. Development of knowledge and society led to the recognition that causes of congenital developmental disorders (CDDs) might be caused by various mechanical effects, foetal diseases, and retarded or arrested development of the embryo and foetus. Based on the analysis of the historical development of hypotheses and theories representing a decisive contribution to this field, we present a survey of the six Wilson′s fundamental principles of teratology. The aim of observing these principles is to get insight into developmental relations and to understand mechanisms of action on the level of cell populations (elementary morphogenetic processes), tissues and organs. It is important to realise that any negative intervention into the normal course of these processes, either on genetic or non-genetic basis, inevitably leads to a sequence of subsequent changes resulting in CDDs. Moreover, the classical toxicologic monotonic dose-response paradigm recently has been challenged by the so-called “low dose-hypothesis”, particularly in the case of endocrine active substances. These include some pesticides, dioxins, polychlorobiphenyls (PCBs), and bisphenol A. Despite modern approaches of molecular biology and genetics, along with top diagnostic techniques, we are still not able to identify the actual cause in more than 65 to 70% of all congenital defects classified as having an unknown etiology. Today CDDs include any birth defect, either morphological, biochemical, or behavioural.

Inappropriate modeling of chronic and complex disorders: How to reconsider the approach in the context of predictive, preventive and personalized medicine, and translational medicine

“…Among 1396 different substances studied, it has been shown that half of the human teratogens are safe in animals. Conversely, almost half of the safe human agents are dangerous (teratogen) in animals, and 1/3 tested agents showed varying results in different species [62][63][64].…”

El mosaico de Bernard – La explicación causal en biología funcional

“…La teratología nos brinda ejemplos de eso (UJházy et al, 2012). La perturbación de los procesos de inducción embrionaria, que son los responsables de la diferenciación de órganos en la ontogenia, puede generar distintas malformaciones; y esas perturbaciones pueden ser apuntadas como causas de dichas anomalías sin que para ello sea necesario conocer la base molecular de tales fenómenos (GILbErT, 1994, p. 513-515;DELSoL & PErrIn, 2000, p. 88-90).…”

Effect of non-ionizing electromagnetic field on the alteration of ovarian follicles in rats

“…The damaging effects of electromagnetic fields depend on the frequency (wavelength), the density of the field, and the duration of radiation (1). Extremely low frequency electromagnetic fields (ELF-EMF), non-ionizing radiation that has a frequency range in home appliances with frequency of 50 or 60 Hz that emit waves with long wavelength (3). Most electrical appliances work in the frequency range between 50 and 60 Hz, and further studies of the impact of electromagnetic radiation on living organisms is being done in this frequency range.…”

“…Most electrical appliances work in the frequency range between 50 and 60 Hz, and further studies of the impact of electromagnetic radiation on living organisms is being done in this frequency range. Fifty Hertz corresponds to a wavelength of 3,500 kilometers, which is close to the Earth’s radius (3). Many studies have been conducted to determine the possible effects of low frequency fields on human health (4–6).…”