KCNH2 and leukemia: Thus, it has been described that various tumours, such as neuroblastoma, small lung carcinoma and leukaemia cell lines12, 13 express an N-terminally truncated splice variant of HERG1, referred to as HERG1B, along with the full-length HERG1 (also termed HERG1A) to form heterotetrameric channels, which show faster deactivation kinetics than those observed for HERG114.