add balcklist slide

Workflow_steps.Rmd

@@ -377,6 +377,33 @@ include_graphics("files/igv_snapshot_4.png")
 ```
 
 
+## Peak Filtering
+
+**blacklist regions**: erroneous signal, artifacts
+
+- extermely high signal
+- present in ChIP input controls
+<p>&nbsp;</p>
+- low mappability
+- short repeats
+
+<p>&nbsp;</p>
+
+\tiny
+Amemiya, H.M., Kundaje, A. & Boyle, A.P. The ENCODE Blacklist: Identification of Problematic Regions of the Genome. Sci Rep 9, 9354 (2019). https://doi.org/10.1038/s41598-019-45839-z
+
+## Peak Filtering
+
+- extermely high signal
+
+```{r, echo=FALSE, fig.align='center', out.width = "200px"}
+include_graphics("files/blacklist.png")
+```
+
+\tiny
+Amemiya, H.M., Kundaje, A. & Boyle, A.P. The ENCODE Blacklist: Identification of Problematic Regions of the Genome. Sci Rep 9, 9354 (2019). https://doi.org/10.1038/s41598-019-45839-z
+
+
 
 ## MultiQC Report