KMT2B-related dystonia is a rare childhood-onset movement disorder marked by pronounced muscle tone and gait abnormalities, which usually commence in the lower limbs and progress upward. It is associated with mutations in lysine-specific methyltransferase 2B (KMT2B) located on chromosome 19q13.12 [1]. KMT2B-related dystonia is most often inherited in an autosomal dominant manner, typically with heterozygous mutations. This evidence concerns the gene KMT2B and movement disorder.