TABLE 2

Association between maternal GCK rs1799884 genotype and maternal glucose levels in pregnancy

Total NMean ± SE plasma glucose level by GCK rs1799884 genotypeEffect size ± SE per T-allele (mmol/l)*P
CCCTTT
FPG (mmol/l)
    European3,8114.55 ± 0.014.59 ± 0.014.63 ± 0.030.03 ± 0.010.001
    Thai1,7064.42 ± 0.014.51 ± 0.024.52 ± 0.080.08 ± 0.02<0.0001
1-h plasma glucose (mmol/l)
    European3,8117.39 ± 0.037.54 ± 0.057.69 ± 0.150.15 ± 0.050.001
    Thai1,7068.25 ± 0.058.35 ± 0.098.54 ± 0.370.11 ± 0.090.24
2-h plasma glucose (mmol/l)
    European3,8116.11 ± 0.026.12 ± 0.046.18 ± 0.110.02 ± 0.040.56
    Thai1,7066.61 ± 0.046.85 ± 0.086.81 ± 0.300.21 ± 0.070.005
  • The European plasma glucose levels by genotype are the mean values across all four field centers. These are presented separately in supplementary Table 1.

  • *The T-allele of GCK rs1799884 is associated with raised fasting glucose in nondiabetic, nonpregnant populations. The T-allele frequency ranged from 17.1 to 18.7% in the European ancestry samples and was 10.3% in the Thai samples.

  • †The effect sizes and P values are from linear regression of maternal glucose level against genotype (coded 0, 1, or 2 T-alleles), with field center (European ancestry only), age, BMI, and mean arterial pressure as covariates. Age, BMI, and mean arterial pressure were measured at a median of 28–29 weeks' gestation, depending on the field center. Mean ± SE values are adjusted for these three covariates. FPG, fasting plasma glucose.