IGFORCE D – igf des or igf 1 is insulin lik-e growth factor 1(igf1) des(1-3) igf -1 lacks the first three amino acids at N terminus of IGF 1 (FOR a total 67 amino acids relative to 70 of IGF-1). Igf des serves as an alternative to solely relying on pituitary gland to make human growth harmones. The pituitary gland decreases function with age . It is shortest and most powerful form of igf 1 .it responsible for growth of skeletal muscle and longs bone in body.