The highest probe target numbers (5 experimental and 225 calculated) have been assigned against mTOR (MTOR, P42345). Next in rank are Histone deacetylase 1 (HDAC1, Q13547) with 2/161 experimental/calculated, Epidermal growth factor receptor (EGFR, P00533) with 7/103 and Estrogen receptor (ESR1, P03372) with 1/92. The larger number for calculated probes reflects their more frequent origin from panel screening papers and consequent higher average compounds: target ratio of 9.8 for the Probe Miner set compared to ~1.0 for experimental probes. For these, the highest assigned target numbers are BRD4 (O60885) and the BRD3/BRD2 (Q15059/P25440) subfamily pair with 18 and 15 probes, respectively. This is a consequence of the declared SGC Probes focus on epigenetic regulators. The family distribution of all annotated targets is shown in Figure .