Precision medicine is part of the logical evolution of contemporary evidence-based medicine that seeks to reduce errors and optimize outcomes when making medical decisions and health recommendations. Diabetes affects hundreds of millions of people worldwide, many of whom will develop life-threatening complications and die prematurely. Precision medicine can potentially address this enormous problem by accounting for heterogeneity in the etiology, clinical presentation and pathogenesis of common forms of diabetes and risks of complications. This second international consensus report on precision diabetes medicine summarizes the findings from a systematic evidence review across the key pillars of precision medicine (prevention, diagnosis, treatment, prognosis) in four recognized forms of diabetes (monogenic, gestational, type 1, type 2). These reviews address key questions about the translation of precision medicine research into practice. Although not complete, owing to the vast literature on this topic, they revealed opportunities for the immediate or near-term clinical implementation of precision diabetes medicine; furthermore, we expose important gaps in knowledge, focusing on the need to obtain new clinically relevant evidence. Gaps include the need for common standards for clinical readiness, including consideration of cost-effectiveness, health equity, predictive accuracy, liability and accessibility. Key milestones are outlined for the broad clinical implementation of precision diabetes medicine.

OBJECTIVE: To characterize metabolites across the range of maternal glucose by comparing metabolomic profiles of mothers with high and low fasting plasma glucose (FPG).RESEARCH DESIGN AND METHODS: We compared fasting serum from an oral glucose tolerance test at ∼28 weeks’ gestation from 67 Northern European ancestry mothers from the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study with high (>90th percentile) FPG with 50 mothers with low (<10th percentile) FPG but comparable BMI. Metabolic data from biochemical analyses of conventional clinical metabolites, targeted mass spectrometry (MS)-based measurement of amino acids, and nontargeted gas chromatography/MS were subjected to per-metabolite analyses and collective pathway analyses using Unipathway annotation.RESULTS: High-FPG mothers had a metabolic profile consistent with insulin resistance including higher triglycerides, 3-hydroxybutyrate, and amino acids including alanine, proline, and branched-chain amino acids (false discovery rate [FDR]-adjusted P < 0.05). Lower 1,5-anhydroglucitol in high-FPG mothers suggested recent hyperglycemic excursions (FDR-adjusted P < 0.05). Pathway analyses indicated differences in amino acid degradation pathways for the two groups (FDR-adjusted P < 0.05), consistent with population-based findings in nonpregnant populations. Exploratory analyses with newborn outcomes indicated positive associations for maternal triglycerides with neonatal sum of skinfolds and cord C-peptide and a negative association between maternal glycine and cord C-peptide (P < 0.05).CONCLUSIONS: Metabolomics reveals perturbations in metabolism of major macronutrients and amino acid degradation pathways in high- versus low-FPG mothers.

Transversions (Tv’s) are more likely to alter the amino acid sequence of proteins than transitions (Ts’s), and local deviations in the Ts:Tv ratio are indicative of evolutionary selection on genes. Whether the two different types of mutations have different effects in non-protein-coding sequences remains unknown. Genetic variants primarily impact gene expression by disrupting the binding of transcription factors (TFs) and other DNA-binding proteins. Because Tv’s cause larger changes in the shape of a DNA backbone, we hypothesized that Tv’s would have larger impacts on TF binding and gene expression. Here, we provide multiple lines of evidence demonstrating that Tv’s have larger impacts on regulatory DNA including analyses of TF binding motifs and allele-specific TF binding. In these analyses, we observed a depletion of Tv’s within TF binding motifs and TF binding sites. Using massively parallel population-scale reporter assays, we also provided empirical evidence that Tv’s have larger effects than Ts’s on the activity of human gene regulatory elements. Tv’s are more likely to disrupt TF binding, resulting in larger changes in gene expression. Although the observed differences are small, these findings represent a novel, fundamental property of regulatory variation. Understanding the features of functional non-coding variation could be valuable for revealing the genetic underpinnings of complex traits and diseases in future studies.

The timing of parturition is crucial for neonatal survival and infant health. Yet, its genetic basis remains largely unresolved. We present a maternal genome-wide meta-analysis of gestational duration (n = 195,555), identifying 22 associated loci (24 independent variants) and an enrichment in genes differentially expressed during labor. A meta-analysis of preterm delivery (18,797 cases, 260,246 controls) revealed seven associated loci and large genetic similarities with gestational duration. Analysis of the parental transmitted and nontransmitted alleles (n = 136,833) shows that 15 of the gestational duration genetic variants act through the maternal genome, whereas 7 act both through the maternal and fetal genomes and 2 act only via the fetal genome. Finally, the maternal effects on gestational duration show signs of antagonistic pleiotropy with the fetal effects on birth weight: maternal alleles that increase gestational duration have negative fetal effects on birth weight. The present study provides insights into the genetic effects on the timing of parturition and the complex maternal–fetal relationship between gestational duration and birth weight.

Context: An obesogenic perinatal environment contributes to adverse offspring metabolic health. Previous studies have been limited by lack of direct adiposity measurements and failure to account for potential confounders. Objective: Examine the joint associations of maternal midpregnancy body mass index (BMI) and glycemia with direct adiposity measures in 10-14 year old offspring. Design and Setting: International, epidemiological study: Hyperglycemia and Adverse Pregnancy Outcome (HAPO) and HAPO Follow-up Study, conducted between 2000-2006 and 2013-2016, respectively. Participants and Main Outcome Measures: In 4832 children, adiposity measures for body mass index (BMI), body fat with air displacement plethysmography, skinfold thickness, and waist circumference were obtained at mean age 11.4 years. Results: Maternal BMI and glucose, as continuous and categorical variables, were the primary predictors. In fully adjusted models controlling for child age, sex, field center, and maternal characteristics, maternal BMI had significant, positive associations with all childhood adiposity outcomes, while maternal glycemia had significant, positive associations with childhood adiposity outcomes except BMI. In joint analyses, and compared with a nonobese, nongestational diabetes mellitus (GDM) reference group, maternal obesity and GDM were associated with higher odds (maternal obesity odds ratio; OR [95% confidence interval; CI], GDM OR [95% CI]; combined OR [95% CI]) of childhood overweight/obese BMI (3.00 [2.42-3.74], 1.39 [1.14-1.71], 3.55 [2.49-5.05]), obese BMI (3.54 [2.70-4.64], 1.73 [1.29-2.30], 6.10 [4.14-8.99]), percent body fat >85th percentile (2.15 [1.68-2.75], 1.33 [1.03-1.72], 3.88 [2.72-5.55]), sum of skinfolds >85th percentile (2.35 [1.83-3.00], 1.75 [1.37-2.24], 3.66 [2.55-5.27]), and waist circumference >85th percentile (2.52 [1.99-3.21], 1.39 [1.07-1.80], 4.18 [2.93-5.96]). Conclusions: Midpregnancy maternal BMI and glycemia are independently and additively associated with direct adiposity measures in 10-14 year old children. The combination of maternal obesity and GDM is associated with the highest odds of childhood adiposity.