Functional genetic screens for enhancer elements in the human genome using CRISPR-Cas9

Abstract

Systematic identification of noncoding regulatory elements has, to date, mainly relied on large-scale reporter assays that do not reproduce endogenous conditions. We present two distinct CRISPR-Cas9 genetic screens to identify and characterize functional enhancers in their native context. Our strategy is to target Cas9 to transcription factor binding sites in enhancer regions. We identified several functional enhancer elements and characterized the role of two of them in mediating p53 (TP53) and ERα (ESR1) gene regulation. Moreover, we show that a genomic CRISPR-Cas9 tiling screen can precisely map functional domains within enhancer elements. Our approach expands the utility of CRISPR-Cas9 to elucidate the functions of the noncoding genome.

Advancing biotechnology with CRISPR/Cas9: recent applications and patent landscape

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CRISPR-based reagents to study the influence of the epigenome on gene expression

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“…Another possibility will be to produce 'custom-made' models for human genetic diseases in which mice will carry a point mutation equivalent to that found in a given patient. Finally, tackling the poorly explored noncoding part of the genome, that is, the noncoding RNAs and regulatory sequences, becomes feasible (Korkmaz et al 2016). The production of new transgenic lines is not a rate-limiting step anymore.…”