Last april , the Center for Genomic Regulation left us a kit with all the equipment and reagents necessary to carry out a practical activity based on electrophoresis for our ESO4 Biology and Geology students. Electrophoresis is a technique that allows us to separate DNA samples by size.

Our ESO4 pupils studied and applied the Agar Electrophoresis technique in the school laboratory.  They started preparing the materials and solutions needed in the protocol with coloured samples labelled as in a possible crime scenario. Next day they were asked to compare the DNA from a Crime Scene (sample labelled EC) to the DNA samples of 3 Suspects (samples labeled S1, S2 and S3).

Here you have a nice presentation with the entire protocol and conclusions, designed by Jose Manuel Bocara from our 4B class:

Pouring the solution of agar gel at 1% to prepare our electrophoresis boxes

Cutting off the gel that went over and removing the comb to create the wells

The syringe and the samples in a microplate

Loading the samples into the wells

Running the gel…

..and observing results!

CONCLUSIONS

• Electrophoresis is a technique that allows us to separate components by size.
• We realized that some of the samples had 2 components and others had 3.
• The yellow component is the smallest and/or the most negatively charged as it moves the furthest through the gel towards the positive anode.
• The blue component is the largest and/or has the least negative charge as it moves the least through the gel.
• Sample  S3 had the same components as the Crime Scene (EC) sample.

Víctor Escarré

Biology and Geology ESO4