Kv7 channels which encoded with KCNQ genes (KCNQ1-5) are a small family of voltage-gated potassium channel, while impressively with critical roles in physiology and disease.Dysfunctions of KCNQ channels and KCNQ gene mutations have been identified to cause a lot of diseases and genetic disorders.Long QT syndrome, a disorder of cardiac repolarisation, of which the most common form, LQT1 is related to KCNQ1 mutation or co-expression of mutant KCNE1 with KCNQ1.Benign familial neonatal convulsions (BFNCs) were reported to be caused by the mutations of brain KCNQ2 and KCNQ2/3 channel.Congenital hearing loss can be associated with Jervell and Lange-Nielsen (JLN) syndrome (one form of LQT1) and mutations in the KCNE1 and KCNQ1 (co expressed in the cell of stria vascularis) or the KCNQ4 (expressed in outer hair cells) genes.KCNQ5 is expressed in skeletal muscle and brain.As co-assembled with KCNQ3, it plays a role in the M-current heterogeneity.Kv7 channels also play newly identified physiological roles in vascular system that attracts increased attention.Modulators of KCNQ channels have the potential to influence neuronal activity in various tissues and are of much interest as therapeutic drug targets for the treatment of a variety of clinical disorders as epilepsy, convulsion, stroke, Alzheimers disease, pain, etc.Thus, the function of KCNQ channels, expressions and mutations of KCNQ genes have been a subject of increasing interest during the last decade.