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@@ -186,6 +186,13 @@ We want to estimate the number of each mRNA molecule in each cell.
 
 [*](https://www.genomescan.nl/wp-content/uploads/2019/10/graphic_UMIs_1.png.webp)
 
+
+## Unique Molecular Identifier (UMI)
+
+\begin{center}
+\includegraphics[width=\textwidth]{./img/umi_vs_read.png}
+\end{center}
+
 ## single-cell RNA Sequencing
 
 ### **3'** mRNA capture