We know that there are perhaps 40,000 unique mutations affecting more than 10,000 genes and that there are 500 of these genes that are bonafide drivers — causes — of cancer. Yet comparatively we have about a dozen targeted medications.

Bradner is contrasting the vast genetic complexity of cancer with the comparatively small number of therapies that precisely target known molecular causes. By citing tens of thousands of mutations, thousands of genes, and hundreds of “driver” genes, he underscores how many distinct, causative biological mechanisms can underlie tumors—often varying by patient and even within a single cancer type. The final comparison (“about a dozen targeted medications”) highlights a translational gap: scientific knowledge about cancer genomics has outpaced the development, approval, and clinical availability of drugs matched to those drivers. The quote functions as an argument for accelerating drug discovery, broadening targetable biology, and improving precision-medicine pipelines so genomic insights yield more actionable treatments.