Prtn3 (proteinase 3) is a serine protease that degrades elastin, fibronectin, laminin, vitronectin, and collagen types I, III, and IV36, whereas Hal (Histidine ammonia-lyase) catalyzes breakdown of histidine, an amino acid shown to improve insulin resistance in obese women37. The gene discussed is HAL; the disease is Insulin resistance.