PerturbAI has emerged from stealth mode with the release of the world’s largest in vivo CRISPR atlas as described in a preprint on Biorxiv. The study profiled over 7.7 million cells from the brains of 74 mice with different cellular knockouts of 1,947 disease-associated genes. The San Francisco-based company’s Perturb-seq platform combines CRISPR perturbations with single nucleus RNA sequencing to look at gene expression.