Combined effect of risk alleles for high fasting glucose from <i>GCK</i> rs1799884, <i>G6PC2</i> rs16856187 and <i>MTNR1B</i> rs10830963 on quantitative traits.

<p>(a) fasting glucose (<i>n</i> = 3,212); (b) 2 h glucose (<i>n</i> = 3,212); (c) HOMA-β (<i>n</i> = 2,304); (d) insulinogenic index (<i>n</i> = 953); (e) first-phase insulin secretion (<i>n</i> = 2,294); (f) second-phase (<i>n</i> = 2,294) insulin secretion. Data shown are mean±SE. Individuals carrying more risk alleles for high fasting glucose tended to have higher glucose levels at both fasting (<i>p</i> = 1.7×10⁻¹³) and 2 h during OGTT (<i>p</i> = 0.0009), lower HOMA-β (<i>p</i> = 0.0011), insulinogenic index (<i>p</i> = 0.0017), first- (<i>p</i> = 1.1×10⁻⁷) and second-phases (<i>p</i> = 0.0321) of insulin secretion.