Two mutants of TBK1, the kinase-dead mutant S172A and the ALS-associated mutant E696K (152) were tested, but neither showed any change from the 50% reduction of cell culture L1 retrotransposition caused by overexpression of the wild-type protein (Additional file 1: Figure S4F). Here, TBK1 is linked to amyotrophic lateral sclerosis.