Goals: To characterize functionally one gene set obtained from down-expressed genes comparing young and elder people fibroblasts in a RNAseq experiment.

Functional enrichment of those genes providesextra information that helps to understand those processes where they act and identify new candidates.

Data: After differential expression analysis we identify 47 down-expressed genes (elder population) in fibroblasts from connective tissue. Included in file “fibro.txt”.

Workflow:

1. Open this file in a text editor and inspect its content.
2. Upload the file in Babelomics through the Upload button. We have to specify the data type: “Id list (Id)”.
3. Select the functional enrichment analysis tool in the menu “Functional / Single Enrichment: FatiGO”.
4. Firstly, we compare our list against the rest of genome. We have to select our data and organism (human).
5. It's possible perform simultaneously several enrichment analysis using different databases. Firstly, we select biological process, and specify those functions annotated with 5 – 300 genes (filtering general and most specific functions).
6. We name the job and execute the task. It may expend about 20 minutes in complete the job.

Questions:

1. How many GO term are significant?
2. We are interested in term “microtubule organizing center organization (GO:0031023)” In our list, which genes are enriched with that function?
3. What means statistical values that appears in this GO term?
4. How do we interpret the graphic that appears under the significant results? What means unpainted terms? And color graduation?