FADS1 and type 2 diabetes mellitus: Conversely, a significant decrease in FADS1 activity was recorded (the C20:4/C20:3 ratio decreased from 26.6 in controls to 8.1 in T2D), indicating impaired synthesis of arachidonic acid from dihomo-γ-linolenic acid (DGLA; 20:3 n-6), which is an omega-6 polyunsaturated fatty acid and a metabolic precursor of anti-inflammatory eicosanoids such as prostaglandin E1.