Overview¶
FireCloud Method: xavier-genomics/stars_crispr_screen
The STARS CRISPR Screen pipeline takes raw pooled reads (in .fastq format) and does the following:
- De-pools samples and generates counts for various genes
- If there are multiple complete runs of the sequencing, combine them and treat the separate runs as replicates.
- Run edgeR to get differential expression for pairs of conditions.
- Combine differential expression results across pairs of conditions.
- Perform STARS analysis to identify top gene/comparison combinations.
The eventual output is a file called full_stars_output.tsv that will look something like the following (with many more genes):
| gene_symbol | comparison | ranks_of_perturbations_up | stars_score_up | average_score_up | p_value_up | fdr_up | q_value_up | ranks_of_perturbations_down | stars_score_down | average_score_down | p_value_down | fdr_down | q_value_down | best_direction | best_p_value | best_fdr | best_q_value | meanLogFC |
| Rpsa | APC_high_vs_APC_low | 64082 | 0.000210041408814 | 0.000105020704407 | 0.999952927331568 | 0.999952927331568 | 0.999952927331568 | 32 | 3.30179612071268 | 1.65089806035634 | 0.001583799156615 | 1 | 0.845436893203888 | down | 0.001583799156615 | 1 | 0.845436893203888 | -9.22135697323133 |
| Mrps14 | APC_high_vs_APC_low | 64080 | 0.0002235959564 | 0.0001117979782 | 0.999950965970383 | 1 | 0.999952927331568 | 34 | 3.27546718199033 | 1.63773359099516 | 0.001670589389036 | 1 | 0.845436893203888 | down | 0.001670589389036 | 1 | 0.845436893203888 | -9.20867956964751 |
| Ubc | APC_high_vs_APC_low | 63860 | 0.001717184829155 | 0.000858592414577 | 0.999607237422771 | 0.999852371376723 | 0.999822461991172 | 254 | 2.40211238241264 | 1.20105619120632 | 0.012126115524174 | 0.915925925925936 | 0.899778481012659 | down | 0.012126115524174 | 0.915925925925936 | 0.899778481012659 | -8.37619589451366 |
There are a number of ways to do CRISPR Screen analyses and we may create more pipelines in the future.