<prompt> Which of the is not a channelopathy -Cystic fibrosisLiddles syndromeTay-sachs diseaseHypokaelemic periodic paralysis  <response>: Ans. is c i.e., Tay-Sachs disease Ion channels provide pores for the passive diffusion of ions across biological membranes.They are often highly selective for a particular ionic species, leading to a classification into sodium Na, potassium K, calcium Ca2, chloride Cland unspecific cation channels. Ion channels serve many functions apart from electrical signal transduction: chem ical signalling Ca2as a second messenger, transepithelial transport, regulation of cytoplasmic or vesicular ion concentration and pH, and regulation of cell volume. Therefore, ion channel dysfunction can cause diseases in many tissues.The list of human diseases known to be associated with defects in ion channels has grown considerably during the past years. This review gives a short overview of known channelopathies, and focuses in particular on recent findings and on channelopathies that have significantly advanced our physiological insight.Known ion channel diseasesChannelGene DiseaseCation channels:CHRNA1 ACHRACHRNA1 Myasthenia congenitaCHRNA4CHRNA4 Autosomal dominant nocturnal frontal lobe epilepsyCHRNB2CHRNB2 Autosomal dominant nocturnal frontal lobe epilepsyPolycystin-2PKD2 Autosomal dominant polycystic kidney disease ADPKDCNGA3CNGA3 Achromatopsia 2 color blindnessCNGB1CNGB1 Autosomal recessive retinitis pigmentosaCNGB3CNGB3 Achromatopsia 3Sodium channels:Navl.lSCN1A Generalized epilepsy with febrile seizures GEFSpNavl.2SCN2A Generalized epilepsy with febrile and afebrile seizuresNavl.4 paralysisQSCN4A Paramyotonia congenitaQ potassium aggressive myotonia, hyperkalemic periodicNavl.5SCN5A Long-QT syndrome, progressive familial heart block type I, Brugada syndrome idiopathic ventricular arrhythmiaSCN1BSCN1B Generalized epilepsy with febrile seizures GEFSpENaCaSCNN1A Pseudohypoaldosteronism type 1 PHA1ENaCbSCNN1B PHAI, Liddle syndrome2 dominant hypertensionENaCgSCNN1G PHAI, Liddle syndromeQPotassium channels:Kvl.lKCNA1 Episodic ataxia with myokymiaKCNQlKvLQTlKCNQ1Autosomal dominant long-QT syndrome Romano-WardAutosomal recessive long-QT syndrome with deafness Jervell-Lange-NielsenKCNQ2KCNQ2 BFNC epilepsy, also with myokymiaKCNQ3KCNQ3 BFNC epilepsyKCNQ4KCNQ4 DFNA2 dominant hearing lossHERGKCNH2KCNH2 Long-QT syndromeKirl.lROMKKCNJ1 Bartter syndromeQ renal salt loss, hypokalemic alkalosisKir2.1IRKKCNJ2KCNJ2 Long-QT syndrome with dysmorphic features Andersen syndromeKir6.2KATpKCNJ11 Persistent hyperinsulinemic hypoglycemia of infancy PHHISUR1SUR1 PHHIKCNE1 MinKISKKCNE1 Autosomal dominant long-QT syndrome Romano-Ward Autosomal recessive long-QT syndrome with deafness Jervell-Lange-NielsenKCNE2MiRPlKCNE2 Long-QT syndromeKCNE3MiRP2KCNE3 Periodic paralysisCalcium channels:Cavl.lCACNA1S Hypokalemic periodic paralysisQ, malignant hyperthermiaCavl.4CACNA1F X-linked congenital stationary night blindnessCav2.1CACNA1A Familial hemiplegic migraineQ, episodic ataxiaQ, spinocerebellar ataxia type 6QRyRlRYR1 Malignant hyperthermia, central core diseaseRyR2RYR2Catecholaminergic polymorphic ventricular tachycardia, arrhythmogenic right ventricular dysplasia type 2 Chloride channels:CFTRABCC7 Cystic fibrosisQ, congenital bilateral aplasia of vas deferensClC-1 CLCNl Autosomal recessive Becker orC1C-5 CLCN5dominant Thomsen myotonia Dents diseaseQ X-linkedC1C-7 CLCN7proteinuria and kidney stones Osteopetrosis recessive orCIC-KbdominantCLCNKB Bartter syndromeQ type IIIBarttin BSNDBartter syndrome typeQ IVGLRA1 associated with sensorineural deafnessGLRA1 Hyperekplexia startle diseaseGABAal GABRA1 Juvenile myoclonus epilepsyQGABAg2 GABRG2 EpilepsyGap junction channels:Cx26GJB2 DFNA3 autosomal dominantCx30 GJB4hearing lossDFNB1 autosomal recessive hearing lossDFNA3Cx31 GJB3 DFNA2Cx32 GJB1 CMTX X-linked Charcot- Marie-Tooth neuropathy 