Slc23a3, also known as the orphan transporter SVCT3, is a member of the human SLC23 family. This family is phylogenetically part of the nucleobase-ascorbate transporter (NAT) family. While its exact function has been somewhat speculative, recent research has shed light on its role [3,4].

One study confirmed that SLC23A3 is a hypoxanthine transporter in the human kidney. LLC-PK1 renal cells and SLC23A3 RNA-injected Xenopus oocytes showed specific patterns of hypoxanthine uptake, with certain inhibitors affecting this uptake [1]. Genome-wide association studies have also linked SLC23A3 to plasma vitamin C levels, identifying it as one of 10 novel genetic loci associated with plasma vitamin C [2]. Additionally, SLC23A3 has been associated with schizophrenia in the Japanese population through a genome-wide association study using microsatellite markers, suggesting it may be a candidate gene for schizophrenia susceptibility [5]. In a transcriptome-wide association study, SLC23A3 was identified as a common candidate gene shared by both total body bone mineral density (TB-BMD) and cigarette smoking, indicating a possible genetic correlation [6]. It was also considered as a functional candidate gene in a study on juvenile myoclonic epilepsy, though no causative variant was detected [7].

In conclusion, Slc23a3 has diverse functions, being involved in hypoxanthine transport in the kidney and potentially associated with plasma vitamin C levels, schizophrenia, osteoporosis-related genetic correlations, and juvenile myoclonic epilepsy. The studies on Slc23a3 contribute to understanding its role in these biological processes and disease conditions, which may provide new insights for further research and potential therapeutic strategies.