Posted by: Johnson Francis on: 26 Feb, 2010
Long QT syndromes (LQTS) are a group of inherited arrhythmogenic disorders characterised by prolonged QT interval and life threatening ventricular arrhythmias. The prevalence of long QT syndrome varies from one in five thousand to one in ten thousand in various regions. The initially described syndromes were an autosomal dominant Romano Ward syndrome and the autosomal [...]
Posted by: Johnson Francis on: 23 Oct, 2009
The gene which is affected in Andersen Syndrome (LQT7) is: a. KCNJ2 b. SCN5A c. KCNH2 d. KCNQ1 Answer: a In Andersen syndrome, KCNJ2 which codes for Ik1 potassium channel (Kir2.1) is affected by a loss of function mutation. This results in a reduced outward potassium current. Andersen syndrome is characterised by long QT, periodic [...]
Posted by: Johnson Francis on: 20 Sep, 2009
The gene which is affected in Andersen Syndrome (LQT7) is: a. KCNH2 b. KCNQ1 c. SCN5A d. KCNJ2 Answer: d In Andersen syndrome, KCNJ2 which codes for Ik1 potassium channel (Kir2.1) is affected by a loss of function mutation. This results in a reduced outward potassium current. Andersen syndrome is characterised by long QT, periodic [...]
Posted by: Johnson Francis on: 26 Jan, 2009
Congenital short QT syndrome is new inherited clinical syndrome which was described by Gussak et al in 2000. (Cardiology. 2000;94:99-102). A gene mutation causing short QT syndrome was first demonstrated by Brugada et al in January 2004. This mutation in HERG (KCNH2) gene was later called as SQT1 and was due to gain in function [...]
Posted by: Johnson Francis on: 06 Dec, 2008
10 LQTS genes have been described from 1991 to 2007. LQT1 gene is KCNQ1 and it encodes for alpha (KvLQT1) subunit of the potassium channel conducting the IKs current. IKs is the slow component of the delayed rectifier current, which in turn is the major repolarizing current during phase 3 of the cardiac action potential. [...]
