IRS1 and Miyoshi myopathy: The most essential genes, as indicated by a more negative efficacy score, included both well-established genes ubiquitous in MM biology, including NFKB1 and PRDM1, but also others such as IRS1. Genes with a high selectivity score included MEF2C, NFKB1, RELB and IRS1. MEF2C and NFKB1 were both essential for MM and had high selectivity scores (Supplementary Table 1b).