In Scottish individuals, a study involving 148 T2DM patients who received metformin treatment for six months found that SLC47A1 rs2289669 had a significant genotype-specific effect on the response to metformin, and HbA1c in patients with the homozygous SLC47A1 rs2289669 A-allele had a significantly lower reduction [8]. The gene discussed is SLC47A1; the disease is type 2 diabetes mellitus.