SLC38A4 and Hyperglycemia: The most relevant CpG site (cg14671384, P = 9.09 × 10–9) locates in the promoter of the SLC38A4 gene (Solute Carrier Family 38 Member 4), which has been reported to be a transporter of cationic and neutral amino acids and closely related with glucagon and hyperglycaemia [32, 33].