Mutations in ThTR-2 have been reported to be associated with thiamine metabolic dysfunction syndrome 2 (THMD2), and the clinical and imaging features of ThTR-2 mutant patients were similar to those of WE, indicating that the syndrome was caused by a genetic disorder of thiamine metabolism (Kono et al., 2009). The gene discussed is SLC19A3; the disease is biotin-responsive basal ganglia disease.