Elongases are a class of enzymes involved in the metabolism of unsaturated fatty acids within organisms, regulating the degree of unsaturation by catalyzing elongation reactions. Family members include various subtypes, characterized by specific active sites and multiple structural domains. These enzymes are expressed in various cells and tissues, particularly in the liver, muscles, and adipose tissue, where they participate in fatty acid synthesis and degradation, energy metabolism, and inflammatory responses. The activity of elongases is regulated by various biological signals and factors both within and outside the cell, and gene expression exhibits tissue specificity. Mutations or dysregulation in expression are closely associated with metabolic diseases such as obesity, diabetes, and cardiovascular diseases.