Part B: Adding a gene extraction step

In this part, you’ll add an “extraction” step to the script. This step will extract the genes from the files represented by variable “A” and save them to a single output file.

If you simply dragged the extraction step and dropped it on the Visual View, it would merge with the current step—an undesirable outcome. To make the extraction step appear underneath the current step, you’ll actually start by adding a step to save the extraction results (Step 1, below), and only then add the extraction step (Step 2).

1. From the Toolkit tab on the right, drag Write to Results File (in the Sequences section) and drop it into the Visual View, just below the existing step.

2. Next, drag the Extract Features function (in the Functions section) onto the Visual View, and drop it on the Select sequence source area. Drop the function when you see the blue box shown below.

The script now appears as follows:

3. In the Extract step, choose gene from the Features drop-down menu.

4. In the Select sequence source area, choose the Variable button. Enter the letter A into the Choose sequence variable box.

5. To the right of the Save Results As button, type in the filename Extracted genes.

6. From the Format drop-down menu, choose Fasta.

7. Press the Run button () to run the script. Click OK to close the Run Completed box.

Proceed to Part C: Translating the extracted genes.