DGCR8 and 22q11.2 deletion syndrome: In the nucleus, primary miRNAs (pri-miRNAs) are transcribed and processed by Drosha and its cofactor DGCR8 (also known as Pasha, located in the DiGeorge syndrome chromosomal region) to generate precursor miRNAs (pre-miRNAs) [24], which are then exported to the cytoplasm [25] and further sliced by Dicer to generate ~ 22 nt mature miRNAs [26].