Abstract: Uncoupling proteins (UCPs) belong to the family of mitochondrial transporter proteins that may uncouple the transport of protons across the inner mitochondrial membrane from electron transport, hence generating heat rather than energy. In mammals， more than five family members have been identified including UCP1, UCP2, UCP3, UCP4 (or BMCP1/UCP5),and UCP5.The UCPs may play an important role in energy homeostasis and have become prominent in the fields of thermogenesis, obesity， diabetes and considered candidate genes for obesity and insulin resistance.Uncoupling proteins (UCPs) belong to the family of mitochondrial transporter proteins that may uncouple the transport of protons across the inner mitochondrial membrane from electron transport, hence generating heat rather than energy. In mammals,more than five family members have been identified including UCP1,they have been as important potential targets for treatment of aging,degenerative diseases,diabetes,and obesity in clinical. Recently, a series of studies showed the polymorphisms of UCPs gene association with the fat metabolismobesity, and diabetes.This review summarizes data supporting the roles of UCP1, UCP2 and UCP3 in energy dissipation,and the genetic variety association with the fat metabolism,obesity and diabetes in humans.

Key words: obesity; diabetes; polymorphisms; UCPs gene