Electrophoretic Movement of DNA Fragments

In the realm of molecular biology, gel electrophoresis stands as a crucial tool, acting as a magnifying glass for DNA fragments. This technique, developed by Bio-Rad Laboratories, is used extensively in various fields, including forensic investigations, gene mapping, and the detection of genetically modified organisms.

The process begins with DNA extraction, where cell walls are broken down, and DNA is released. The purification step follows, removing unwanted molecules to ensure the DNA is ready for analysis.

Next, DNA samples are loaded into an agarose gel, a seaweed-based material that forms a gel-like substance when mixed with a buffer solution. The agarose gel acts as an obstacle course for the DNA fragments, allowing for their separation based on size.

An electric field is created within the gel by connecting electrodes to a power supply, acting as the driving force for the DNA molecules. As the DNA fragments race through the gel, smaller fragments move faster than larger ones, a fact that is instrumental in their separation.

Band formation occurs during electrophoresis, with visible bands representing different sizes of DNA fragments. By analysing the position of these bands, scientists can determine the length of DNA fragments. This is further aided by the use of DNA ladders, which help estimate the sizes of unknown DNA fragments.

By combining DNA ladders, band position analysis, and mobility calculations, the code of DNA fragments' sizes and molecular weights can be cracked. Larger fragments have a more extended structure and slower mobility, making them easier to identify in the resulting band pattern.

The electrophoresis process is a cornerstone of molecular biology and biotechnology, helping scientists unlock the secrets of our genes and understand how they work. It plays a pivotal role in unravelling the complexities of DNA, providing a clearer picture of our genetic makeup and its role in health and disease.