SOS2 and Noonan syndrome: Although both hypertrophic cardiomyopathy and chylothorax are common in Noonan's syndrome [4], no variants have been identified in the genes related to Noonan syndrome (PTPN11, SOS1, RAF1, RIT1, KRAS, NRAS, SHOC2, CBL, BRAF, SOS2, MRAS, RRAS, LZTR1, RRAS2, HRAS, MAP2K1, MAP2K2, and PPP1CB) by a targeted next-generation sequencing panel testing.