Infographic DNA extraction
- In the Freezers, thousands of small pieces of animal bodies, the tissue samples, are stored.
- For genetic analysis, the DNA, the animal's genetic material, has to be isolated from the samples. This is done in the lab, step by step.
- Taking the tissue sample out of the freezer.
- Cutting a tiny piece from of the sample at the lab bench...
- ...and inserting it into a tube.
- Adding digestive enzymes and a detergent solution with a pipette.
- The tube is placed inside a thermoshaker. Inside this device, the tissue sample is digested with a combination of heat, movement and digestive fluids, almost as in a real stomach.
- This is necessary, because the DNA is well protected and tightly wrapped inside the cell nucleus.
- To release the DNA out of the cell, the digestive enzymes break down the cell’s proteins. The detergent solution dissolves the fatty outer layer – the membrane – of the cell and the nucleus.
- Thus, the DNA is extracted and floats inside the digested tissue sample. A strand from a single cell is quite long. A human strand, for example, is about 2 metres long
- Now, the digested, liquid tissue sample is put inside the DNA extraction robot. It takes over from here.
- First, the robot filters the tissue sample.
- The DNA gets caught on the filter. The robot rinses repeatedly all other remaining cell components out with various liquids.
- Finally, the robot rinses with water. The cleansed DNA is released from the filter and is collected into a new tube.
- The DNA is now ready for genetic analyses.