SLC22A12 and hypouricemia, renal: Although this GLUT9 variant is extremely rare (i.e., minor allele frequency was .000004–.000007 according to the NCBI dbSNP), considering a recent study reporting that a functionally-null intronic variant (c.506+1G>A) in URAT1 is a causative factor for RHUA type 1 (Kawamura et al., 2020), our discovery supports the notion that genetic variations in the intronic (non-cording) regions of GLUT9 as well as URAT1 should also be kept in mind during diagnostic procedures for renal hypouricemia.