These two transporters are widely expressed in human tissues, and the intracellular thiamine deficiency caused by THTR-1 mutation can be compensated by THTR-2 and passive transport in most tissues.13, 14 However, THTR-1 is the only known transporter in bone marrow cells, pancreatic beta cells, and some cochlear cells, which is the etiology of the clinical typical triad of TRMA syndrome.15 Here, SLC19A2 is linked to Thiamine deficiency.