This lecture reviews a few basic facts about genetics and DNA. There are also links to web resources in case you need to know more. You can also check the bibliography for the course.
A good way to understand molecular genetics and its importance is to understand the human genome project. There is a lot of information available from the Department of Energy. Here is a primer on molecular genetics available on the web. There is also a pdf version there which can be printed out.
The reason that DNA functions the way it does is due to its unique geometrical structure. Here are some close up views of DNA structure.
The big breakthrough in thinking about genetic information as digital
information came with the landmark paper by
Watson and Crick in 1953. This is a very short paper and easy to
read. It reminds you that some important discoveries are based on
simple observations.
A big clue for Watson and Crick was an x-ray diffraction photo of the B form of purified DNA fibers. This photo was obtained by Rosalind Franklin in the laboratory of Maurice Wilkins. The inner cross pattern of spots indicated to Watson and Crick that DNA was some sort of helix.
In the human organism, DNA is organized into 23 pairs of chromosomes. Part of the Human Genome Project is to locate genes on these chromosomes. Chomosomes are tightly wound strands of DNA. The strands are very long and without the presence of certain enzymes, DNA would become tangled and knotted.
The key to understanding the effect of genetics on health and disease is to understand that the genes on DNA code for proteins. It is these proteins which determine the characteristics of organisms. Proteins will be discussed in the next lecture.
You can peruse other images, posters and figures on the DOE site.
