Because there are conflicting data in the field regarding the role of gap junctions in essential tremor (ET) (Loewenstein, 2002; Long et al., 2002; Martin and Handforth, 2006), we asked whether downregulation of innexins [subunits of gap junctions in insects (Phelan, 2005)] in R21G03-Gal4-expressing neurons could cause tremor. This evidence concerns the gene LGALS4 and essential thrombocythemia.