TUBB4A and Dystonia: Dystonia occurring with no other neurological signs on clinical examination and normal neuroimaging is currently classified as “primary isolated dystonia.” Mendelian forms of this primary isolated dystonia have been associated with several genes (TOR1A [MIM 605204],2THAP1 [MIM 609250],3CIZ1 [MIM 611420],4ANO3 [MIM 610110],5GNAL [MIM 139312],6 and TUBB4A [MIM 602662]7, 8), all of which are inherited in an autosomal-dominant fashion.