Definitions for commonly used terms

Dataset-a dataset includes all the screens associated with a particular publication or pre-publication document. A single publication may have 1-100s of screens associated with it.

Screen-a set of gene level quantitative scores derived from a single experiment. Each screen is assigned a number followed by the PubMed ID (e.g. 1-PMID26627737) to ensure publications with mulitple screens have a unique identifier for each individual screen.

Negative Selection Screen-Screen for identifying genes whose perturbation results in cells not surviving the selection mechanism. Typically, the associated phenotype is “viability” or “resistance” and the mutants are underrepresented/depleted after selection. This fitness screen may be used to determine gene essentiality. May also be referred to as a dropout screen.

Positive Selection Screen-Screen for identifying genes whose perturbation results in cells surviving the selection mechanism, e.g drug exposure. Typically, the associated phenotype is “viability” or “resistance” and the mutants are overrepresented/enriched after selection. This fitness screen may be used to detect drug resistance and identify drug targets. Also known as an enrichment screen.

Phenotype Screen-Screen for identifying genes whose perturbation results in other non-fitness phenotypes, such as altered nuclear size or detection of a selectable marker for measuring activity of a particular pathway.

CRISPRn/Knockout Library -A gRNA library designed to generate knockout cells or animals with loss-function mutations within the targeted genes.

CRISPRa/Activation Library -A gRNA library used in conjunction with a modified Cas enzyme fused to protein domains that turn gene expression on, thereby activating gene expression of target genes.

CRISPRi/Inhibtion Library -A gRNA library used in conjunction with a modified Cas enzyme fused to protein domains that turn gene expression off, thereby repressing or inhibiting gene expression without knocking the gene out.

Analytical Method -The statistical or computational method used by the authors to determine which genes in their screen represent hits. These can range from straight-forward read counts to very complex scoring systems with associated confidence values. For a detailed list of the analytical methods currently in ORCS and the relevant references for these methods go here

 
orcs/definitions.txt · Last modified: 2019/10/14 15:34 by rose