A new method uses genetic clues to uncover new uses for existing medications1.
Repurposing approved drugs is faster and cheaper than making new medicines. In the new approach, researchers first identify genetic variants tied to the condition they aim to treat. They then find another condition with similar genetics for which drug treatments are available.
To streamline the method, the researchers confined their dataset to the ‘druggable genome’ — a set of genes for proteins that make good drug targets. These genes appear in the Drug Gene Interaction Database. After combing the literature, the researchers updated the list with 2,282 additional genes, bringing the total to 4,479.
By consulting more than 2,000 genome-wide association studies, the researchers found 9,178 significant associations between genomic regions and conditions of various types, including cardiovascular diseases, cancers and nervous system disorders. Together, these regions contain 1,427 druggable genes, the team reported 29 March in Science Translational Medicine.
The researchers examined the genes for pairs of conditions with druggable genes in common. They found 144 approved drugs that appear promising for treating other conditions: For instance, some drugs approved for cancer show promise as therapy for psychiatric conditions.
The same analysis also revealed that in 74 cases, the genetic variants tied to a condition are the molecular targets of the drugs used to treat that condition. This finding indicates that genome-wide association studies could point to drug targets for conditions that have no available treatments.
Researchers used this method to design a new array, called Illumina DrugDev, that detects variants in druggable genes. They can use this array to identify variants that are likely to be good drug targets for a particular condition.