Jijun Cheng, Wen Pan, Christine Roden, Zhuo Chen and Jun Lu
Only ~2% of the human genome encodes proteins. The functions of the vast majority of non-coding sequences, transcribed or non-transcribed, remain largely unknown. Powered by next generation sequencing and evolving high through-put biochemical technologies, continuing efforts have been devoted to the biochemical annotation of genomic regions based on their transcription activity, DNase-I hypersensitivity, transcription factor binding, chromatin modifications and replication domains. However, biochemical annotation does not equal functional roles in molecular control or cellular behavior. While these genome-scale biochemical data pave the way for deciphering the noncoding genome, high-throughput mapping technologies are required to assign functional roles to specific noncoding elements. Here, we review the use of CRISPR-based technologies in functional screens of noncoding genomic elements, with a focus on the Molecular Chipper technology.