DNA - deoxyribonucleic acid

The so-called DNA structure was discovered in 1953.

What does that mean?
Each living matter consists of a multitude of cells. Each of these cells has a nucleus that contains the hereditary pattern. It is possible to analyze the tiniest details of an organism or even to manipulate the hereditary pattern with the help of that organism's DNA structure. An exact identification of living matter is possible with the analysis. In future, the world of electronics will notice more frequent encounters with the abbreviation "DNA." Scientists have even begun to develop DNA computers at this time.

Discovery:
During the first half of the 20th century, science mainly dealt with nuclear physics. Those early scientists were involved in the attempt to decode the secrets of the atom and to research the smallest parts of the universe.

Two scientists, James Watson and Francis Crick, discovered the DNA structure and thus established a new branch of science known as molecular biology in 1953. With the help of molecular biology, Watson and Crick made the research of the latest mysteries of life and the nearly boundless manipulation of those mysteries possible. Cloning genes, gene banks and genetic identification was entirely inconceivable three decades ago. In the future, thanks to the discovery of DNA, many illnesses may be cured or prevented. Certainly this knowledge may also have disastrous consequences in the wrong hands.

The structure of a cell:
Cells are the foundation of all living matter. Most of them are tiny structures with only few thousandth of a millimeter in diameter.

The human body consists of about 100,000 billion cells. These cells can just be imagined as simple, small bags filled with different vital substances such as proteins, nucleic acids, fats and carbohydrates, necessary for different aspects of life. In the interior of the cell there can be found one of the most important parts – the nucleus, without which the cell couldn't exist. The hereditary pattern is contained here in chromosomes.

These cellular components contain the genes that consist of deoxyribonucleic acid (DNA). In a human germ cell there are 23 chromosomes; each of them contains about 100,000 genes.

The DNA structure:
DNA has two essential properties: It stores the information needed to build or to maintain living matter and it can replicate itself. The DNA molecule is actually very long, although it is altogether much too small to be seen in an optical microscope. Its structure suggests that of a twisted rope ladder with millions of rungs. In the DNA there are only four bases: adenine (A), thymine (T), cytosine (C) and guanine (G). The rungs consists of two bases per rung (either A and T or G and C). When a DNA cord splits like a zip lengthwise, the missing half on either side always completes a new DNA strand by corresponding to the old building plan. The two newly built double-stranded cords look exactly like the original one in their succession of bases. Identical cells are produced through this cell division.

Genetic identification:
Closely related people have similar DNA band patterns, while unrelated people have different ones. The individual bands correspond to the so-called "cell sequences" in the DNA. Through radiation the bands are exposed onto a film, in a process known as gel electrophoresis.

Such genetic fingerprints that result from the patterning of DNA bands can be used for affiliation proceedings and for forensic medicine. Only a small sample of blood, sperm or any other body tissue, such as a hair, for example, is needed.

Combating crime through DNA fingerprints began in England in 1987. To track down a murderer, blood samples were taken from about 5000 men.

Future:
The problem of many computer users is that greater storage capacity is increasingly necessary. Scientists are developing a DNA computer following the biological model of the DNA molecule. Such a computer would have enormous advantages, low energy consumption, and extremely high storage density. One single cubic centimeter of DNA liquid would be able to store up to a trillion giga bits. Do the math... Wow!