Link to video tutorial on PCR, restriction enzyme digestion and DNA electrophoresis. Ignore any comments in the tutorial about using the ‘photo’ feature to capture images, as that feature is no longer supported. Use screenshots instead (see below). The tutorial uses the Cystic Fibrosis case as an example. Control sequences mentioned in the tutorial are now included inside the Case A folder, for each of the three families. There is no longer a separate ‘Control’ folder, so to follow along with the tutorial, use one of the three family folders (Case A Brown family, Case A Jones family, or Case A Smith family).

Going through Part 1 of the CRISPR exercise is another way to learn the steps of restriction enzyme digestion and DNA electrophoresis, using both plasmid DNA and oligonucleotides. This exercise includes detailed instructions and screen shots (click here and here for examples).

Using screenshots to capture images

Older versions of the Case It simulation had a ‘photo’ feature enabling users to take photos of gels and other images. This feature is no longer supported, so it is necessary to use other screen capture applications, such as those that come with the Windows and Mac operating systems.

Snipping Tool (and the newer Snip & Sketch) allows you to capture portions of your screen on Windows computers. Open one of these applications, click ‘New’, and drag the screen to capture an image. The image can then be saved in various formats, although .png is preferred.

For the Mac, one way to capture the screen is to use the Preview application. Open Preview, then select ‘Take Screenshot’ from the File menu. There are three options: From Selection, From Window, and From Entire Screen. The first option is the easiest way to capture an image. The image can then be saved as a .png file. The Screenshot app (formerly Grab) can also be used to capture the screen.