Congenital anomalies from a physics perspective. The key role of “manufacturing” volatility

Genetic and environmental factors are traditionally seen as the sole causes of congenital anomalies. In this paper we introduce a third possible cause, namely random “manufacturing” discrepancies with respect to “design” values. A clear way to demonstrate the existence of this component is to “turn off” the two others and to see whether or not there is still remaining variability. Perfect clones raised under well controlled laboratory conditions fulfill the conditions for such a test. Carried out for four different species, the test reveals a variability remainder of the order of 15% in terms of coefficient of variation (i.e. ratio of standard deviation to average, subsequently denoted by CV). As an example, the CV of the volume of E. coli (Escherichia Coli) bacteria immediately after binary fission is of that order.