Exploring genomic regions in Ensembl, Demo
Start at the Ensembl front page, ensembl.org. You can search for a region by typing it into a search box, but you have to specify the species.
To bypass the text search, you need to input your region coordinates in the correct format, which is
chromosome, colon, start coordinate, dash, end coordinate, with no spaces for example:
human 4:122868000-122946000. Type (or copy and paste) these coordinates into either search box.
Press Enter or click Go to jump directly to the Region in detail Page.
Click on the button to view page-specific help. The help pages provide text, labelled images and, in some cases, help videos to describe what you can see on the page and how to interact with it.
The Region in detail page is made up of three images, let’s look at each one in detail.
- The first image shows the chromosome:
The region we’re looking at is highlighted on the chromosome. You can jump to a different region by dragging out a box in this image. Drag out a box on the chromosome, a pop-up menu will appear.
If you wanted to move to the region, you could click on Jump to region (### bp). If you wanted to highlight it, click on Mark region (###bp). For now, we’ll close the pop-up by clicking on the X on the corner.
- The second image shows a 1Mb region around our selected region. This is always 1Mb in human, but the fixed size of this view varies between species. This view allows you to scroll back and forth along the chromosome.
You can also drag out and jump to or mark a region.
Click on the X to close the pop-up menu.
Click on the Drag/Select button to change the action of your mouse click. Now you can scroll along the chromosome by clicking and dragging within the image. As you do this you’ll see the image below grey out and two blue buttons appear. Clicking on Update this image would jump the lower image to the region central to the scrollable image. We want to go back to where we started, so we’ll click on Reset scrollable image.
- The third image is a detailed, configurable view of the region.
Here you can see various tracks, which is what we call a data type that you can plot against the genome. Some tracks, such as the transcripts, can be on the forward or reverse strand. Forward stranded features are shown above the blue contig track that runs across the middle of the image, with reverse stranded features below the contig. Other tracks, such as variants, regulatory features or conserved regions, refer to both strands of the genome, and these are shown by default at the very top or very bottom of the view.
You can use click and drag to either navigate around the region or highlight regions of interest, Click on the Drag/Select option at the top or bottom right to switch mouse action. On Drag, you can click and drag left or right to move along the genome, the page will reload when you drop the mouse button. On Select you can drag out a box to highlight or zoom in on a region of interest.
With the tool set to Select, drag out a box around an exon and choose Mark region.
The highlight will remain in place if you zoom in and out or move around the region. This allows you to keep track of regions or features of interest.
We can edit what we see on this page by clicking on the blue Configure this page menu at the left.
This will open a menu that allows you to change the image.
There are thousands of possible tracks that you can add. When you launch the view, you will see all the tracks that are currently turned on with their names on the left and an info icon on the right, which you can click on to expand the description of the track. Turn them on or off, or change the track style by clicking on the box next to the name. More details about the different track styles are in this FAQ: http://www.ensembl.org/Help/Faq?id=335.
You can find more tracks to add by either exploring the categories on the left, or using the Find a track option at the top left. Type in a word or phrase to find tracks with it in the track name or description.
Let’s add some tracks to this image. Add:
- Proteins (mammal) from UniProt – Labels
- 1000 Genomes - All - short variants (SNPs and indels) – Normal
Now click on the tick in the top left hand to save and close the menu. Alternatively, click anywhere outside of the menu. We can now see the tracks in the image. The proteins track is stranded, so you will see two tracks, one above and one below the contig, representing the proteins mapped to the forward and reverse strands respectively. The variants track is not stranded, so is found near the bottom of the image.
If the track is not giving you can information you need, you can easily change the way the tracks appear by hovering over the track name then the cog wheel to open a menu. To make it easier to compare information between tracks, such as spotting overlaps, you can move tracks around by clicking and dragging on the bar to the left of the track name.
Now that you’ve got the view how you want it, you might like to show something you’ve found to a colleague or collaborator. Click on the Share this page button to generate a link. Email the link to someone else, so that they can see the same view as you, including all the tracks you’ve added. These links contain the Ensembl release number, so if a new release or even assembly comes out, your link will just take you to the archive site for the release it was made on.
To return this to the default view, go to Configure this page and select Reset configuration at the bottom of the menu.