Poster Presentation 44th Lorne Genome Conference 2023

Analysing arrayed CRISPR screen data (#221)

Waruni Abeysekera 1 2 , Ngee Kiat 1 2 , Rebecca Feltham 1 2 , Gordon Smyth 1 3
  1. Walter and Eliza Hall Institute of Medical Research, Melbourne, VICTORIA, Australia
  2. Department of Medical Biology, The University of Melbourne, Parkville, VICTORIA, Australia
  3. School of Mathematics and Statistics, The University of Melbourne, Parkville, VICTORIA, Australia

Arrayed CRISPR screens are widely applied to identify the effect of gene knockout on cellular phenotype. Here, we describe some data relative to an arrayed CRISPR screen experiment that screened nearly 800 genes to study the changes of cell death and levels of cytokines IL-1β and IFN-β when each gene is knocked out. The experiment was designed in 96-well plates and contained targets, negative controls and positive controls. Negative controls were the wells infected with a negative control virus that does not target any known gene and so the tested biology should not be affected whereas positive controls were the well infected with positive control virus that targets the gene Aim2 that is known to have an effect on the tested biology when knocked out.  We propose a comprehensive statistical analysis approach based on linear models to assess differential abundance of cell death measured by Cytotox Green, and to assess differential absorbance levels of IL-1β and IFN-β, between targets and controls. Empirical bayes moderation is used to modify the resulting t-statistics of the linear models based on shared variance information between well plates since the experiment consisted of multiple well plates. Statistical software R is used for model fitting and graphical illustrations of results.