Specific Aims: To compare metformin pharmacokinetics in monozygotic and dizygotic twin pairs.
Comparing renal clearance of metformin in monozygotic and dizygotic twins will allow us to
better understand the influence of heredity on variation in renal elimination. Furthermore,
genotyping renal transporter genes in monozygotic and dizygotic twin pairs with significant
differences in renal clearance of metformin may give us insight into the genes responsible
for this variability.