The seed oil of Euphorbia lathyris L. contains a series of macrocyclic diterpenes known as Euphorbia L-factors. They are the current industrial source of ingenol mebutate, which is approved for the treatment of actinic keratosis, a pre-cancerous skin condition. Our research focuses on the biosynthesis of Euphorbia L-factors, which is required for its biotechnological production. Transcriptome analysis of the mature seeds of E. lathyris L. helps us to discover genes and enzymes involved in the biosynthetic pathways of Euphorbia L-factors.