Genetic Bases Of Long Qt Syndrome

The discovery of the genetic basis of LQTS started in the early 1990s with the mapping of four LQTS loci on chromosomes 11, 3, 7, and 4[5] (OMIM IDs: 192500, 152427, 603830, 600919) (Table 1). Subsequently, the gene on chromosome 11 (LQT1) was identified as KCNQ1 by Wang et al.[6] using positional cloning whereas the candidate gene approach led to the identification of KCNH2 and SCN5A as the genes on chromosomes 7 (LQT2) and 3 (LQT3).[7,8] More recently, mutations in two additional genes on chromosome 21, KCNE1 (LQT5; OMIM id: 176261) and KCNE2 (LQT6; OMIM id: 603796), were reported. All the LQT1-3 and LQT5-6 genes encode for cardiac ion channel subunits. Based on these evidences, LQTS was initially considered a disorder specifically affecting plasmalemmal ion channel controlling the cardiac excitability. However, recent data show that the gene of LQT4 is ANK2: an intracellular protein called ankyrin involved in ion channels anchoring to the cellular membrane (see below).[9]

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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