Reference books claim that the DNA structure was “proven” in 1953 by a publication by James Watson and Francis Crick. The famous photo_51 served as the main basis for this. Wikipedia states: “Photo 51 is a Laue diagram of DNA taken by Raymond Gosling, a doctoral student of X-ray crystallographer Rosalind Franklin, at King’s College in May 1952[, which was generated using X-ray diffraction. It was of fundamental importance[2] for the discovery of the DNA double helix structure by James Watson and Francis Crick[3] at the University of Cambridge.”
On the basis of this photo, a certain structure was assumed and the model of a double helix was derived from it and represented graphically. However, Watson and Crick never directly observed the DNA double helix in a real three-dimensional representation. Against this background, the fundamental question arises as to how one can speak of proof here if it is primarily a case of modelling on the basis of indirect measurement data.
In the following, reference is made to electron micrographs from a publication from 2012 (number 1) and from a publication from 2015 (number 2).
Based on these images, everyone can form their own judgement as to whether the structure of a double helix with the postulated sequence of nucleotides and the four bases adenine, guanine, cytosine and thymine can actually be recognised. In my judgement, no double helix structure can be identified in these images. Interpreting such a structure into these images seems extremely questionable to me, especially from a scientific point of view.
Another important aspect that is often not sufficiently taken into account, especially in electron microscope images, is the alteration of the DNA sample due to the necessary sample preparation. Multi-stage chemical and physical processes are required to enable electron microscopic imaging in the first place. This raises a central question: What changes does the DNA undergo as a result of this complex sample preparation?
A similar problem also arises with photo_51. To produce this image, the DNA was irradiated with X-rays over a period of around 62 hours. Here, too, a crucial question arises: What structural or chemical changes were caused in the DNA by this prolonged irradiation?
A central problem of science today is that many hypotheses and models are presented as proven facts. Originally developed as mental tools for interpreting data, these models are increasingly treated as facts without critical scrutiny.
This narrows the scientific discourse: basic assumptions are rarely scrutinised, alternative explanations are rarely considered and methodological uncertainties are often concealed. Instead of constant scrutiny, there is an implicit consensus that stabilises existing models without critically examining them. This weakens the ability of science to realistically assess its own assumptions and limitations.
This is particularly evident in virology and genetics, where many hypotheses are presented as certain, while decisive control experiments that would allow the hypotheses to be verified or possibly refuted are omitted.
Further information on this and other topics can be found on the science platform NEXT LEVEL – Wissen neu gedacht.
