SLC19A2 and myopia: In the present study, we found that with the increase of myopia induction time, thiamine content in guinea pig choroidal tissues was elevated at the highest level at 4 weeks, and thiamine level decreased but was still higher than that of control group at 6 weeks of modeling; according to the mRNA and protein expression levels, SLC19A3 transporter protein was firstly highly expressed at 2 weeks, and then both SLC19A2 and SLC19A3 were highly expressed at 4 weeks, and then lowly expressed at 6 weeks, suggesting that thiamine was co-regulated by SLC19A2 and SLC19A3 is even more obvious.