subjects with undiagnosed diabetes might have been included in that population. However, we believe it is unlikely this would have affected the results for two reasons. First, when we reproduced our analysis using only women with glycated hemoglobin lower than 6.0%, we obtained similar results. Second, we were able to replicate our novel HK1 findings in the validation cohort in which OGTT was used to eliminate diabetic participants. Although HK1 polymorphisms are associated with glycated hemoglobin levels, the functional consequences of these polymorphisms needs to be established. In this report, we demonstrate that glycated hemoglobin levels in non-diabetic women are affected by genetic variation at the GCK, SLC30A8, G6PC2 and HK1 loci. While associations at the GCK, SLC30A8 and G6PC2 loci confirm or extend previous work done on the genetic basis of diabetes or fasting glucose, our replicated findings at HK1 are novel. 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