Does amiodarone reduce the prevalence of T wave alternans in a population with ventricular tachyarrhythmias?
The prevalence of TWA was decreased in a chronic ventricular tachyarrhythmic population receiving amiodarone as compared with a population not receiving amiodarone.
We identified two novel genes, SOS2 and LZTR1, associated with Noonan syndrome, thereby expanding the molecular spectrum of RASopathies. Mutations in these genes are responsible for approximately 3% of all patients with Noonan syndrome. While SOS2 is a natural candidate, because of its homology with SOS1, the functional role of LZTR1 in the RAS/MAPK pathway is not known, and it could not have been identified without the large pedigrees. Additional functional studies are needed to elucidate the role of LZTR1 in RAS/MAPK signalling and in the pathogenesis of Noonan syndrome.