Genetics is the last time one of the most important and probably the fastest growing fields in biology and medicine. Who has not heard about stem cells, transgenic food and increasingly popular genetic testing to determine fatherhood? I guess everyone older than 12 years knows what DNA and what function it performs in all living organisms. But I can bet that hardly anyone knows the story of Rosalind Franklin - a woman whose research on the structure of DNA are the basis of everything we know today about this remarkable chemical. 
Rosalind Franklin was born in 1920 in London and from an early age showed an interest in science. At age 21 she graduated from Newnham College. Obtaining a degree at the time of World War II contributed for a career in the British Society for Research Coal utilization and the studies that were conducted there, the nucleus of a dissertation, which she completed five years later a doctorate in the field of physical chemistry at Cambridge University. In January 1951 she started work at King's College London, where her immediate boss was Maurice Wilkins, who at that time dealt with rentgenograficznymi research on the structure of DNA. Rosalind Franklin Wilkins continued its pioneering experiments, while improving the way a very modern X-ray crystallography at that time . It was Franklin perseverance in improving research methodology has been key to the discovery of DNA structure. Previously it was thought that deoxyribonucleic acid (DNA) is a kind of bond linking protein molecules, although it was not known how. When they discovered that the four nitrogenous bases - adenine, thymine, guanine and cytosine - are responsible for the transmission of genetic information began to wonder how all these elements are interconnected. To solve this puzzle to a great extent contributed the results of Rosalind Franklin. Roentgenograms of the sodium salt of DNA taken by Franklin provide evidence that the molecule has a helical structure. Famous photo 51 of 1952., Which Wilkins showed James D. Watson without knowledge, let alone consent, Rosalind Franklin became the basis Watson spark of genius (not without the help of Wilkins, who explained to him basic laws of diffraction, which is based on the method of X-ray crystallography).
Big X, which was printed in the X-ray, according to the laws of physics came from the rays reflected from each atom molecule to build a helix. Watson was not yet noticed that this is a double helix. Clearer structure in the shape of diamonds above, below and on the sides of the shape of X according to Watson, was a reflection of helix extension, though today, experts know that they come from regularly repeating sugar-phosphate structure located on the outer ends of the DNA. Different shades of gray in the picture correspond to the strata through which the radiation had to pass. In this way the researchers were able to calculate distance between molecules. An important detail is the lack of the fourth layer (layer 4), due to the fact that it was in that place intersect two helices. Watson, who had been with Francis Crick worked on defining the structure of DNA, photography and shared their thoughts with a colleague and together they managed to build a correct model of DNA. Considerable knowledge on this subject is also provided them with a report to the Medical Research Council written by Franklin in 1952., Which included the information about the phosphate particles are outside the DNA ladder. Earlier, Watson and Crick has long rejected this theory, which, for what was excellent chemist Franklin
is quite obvious - hydrophilic rules should be placed inside the shell of hydrophobic sugar-phosphate, in order to protect them, the more so because after all they are factors encoding genes. When, however, failed to create a model of nitrogen bases on the outside, have benefited from the opinion of Rosalind Franklin. We all know the result. 25 April 1953 year Nature published the article describing the model of DNA built by Watson and Crick. The authors are not taken into account the person in it, Rosalind Franklin, as a key to this discovery, although they mentioned that benefited from her research in creating the model. In the same issue of Nature also included Franklin article about the structure of DNA containing a roentgenogram made by it that treat editors as a support for the main article in the Watson and Crick. Sam Franklin wrote that Mr Watson and Crick played an important role in this groundbreaking discovery. Maybe that's why today, everyone knows their names, but totally do not know who was Rosalind Franklin.
sad thing is that when Watson, Crick and Wilkins received in 1962 years Nobel Prize in medicine for his research on nucleic acids, Rosalind Franklin had not lived for four years. She died at age 37 of ovarian cancer, which most likely was caused by continuous exposure to X-rays. 
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