rs7754840

This association study examined 43 diabetes-related SNPs in relation to diastolic dysfunction and cardiovascular disease across two Swedish cohorts. HNF1B rs757210 (T-allele) was the main finding, associated with prevalent diastolic dysfunction in both the discovery cohort (MPP-RES; OR 1.21, P=0.024) and replication cohort (VARA; OR 1.38, P=0.042), and with increased risk of incident CVD (HR 1.05, P=0.042) but not CHF over 30+ years of follow-up.

Two-stage case-control study of 1,429 pregnant women in Southern China examining MTNR1B gene variants and gestational diabetes mellitus (GDM) susceptibility. SNP rs10830963 was significantly associated with increased GDM risk in the combined analysis (additive model OR=1.36, 95%CI=1.17-1.59, P<0.001; dominant model OR=1.45, 95%CI=1.15-1.83, P=0.005). The rs10830963 variant showed interaction with maternal age and BMI in contributing to GDM risk.

This comprehensive review synthesizes literature on gestational diabetes mellitus (GDM), demonstrating its complex multifactorial etiology involving genetic factors (SNPs in GCKR, KCNQ1, MTNR1B, TCF7L2), epigenetic modifications (DNA methylation and microRNA expression), and alterations in microbial composition across multiple body sites. While certain SNP variants are associated with GDM phenotypes globally, genetic predisposition alone does not explain disease development; lifestyle factors can modify epigenetic signatures and microbiota composition to modulate risk. Evidence indicates genes, epigenetic alterations, and microbiota can transfer from mother to offspring with long-term health consequences.

A case-control study of 674 GDM patients and 690 controls combined with a meta-analysis found that the G allele of rs10830963 and T allele of rs1387153 in MTNR1B are significantly associated with increased risk of gestational diabetes mellitus (GDM). Meta-analysis of 6 studies showed rs10830963 G allele increased GDM risk in co-dominant model (OR 1.62, 95% CI 1.34-1.94) and rs1387153 T allele increased risk in co-dominant model (OR 1.53, 95% CI 1.26-1.86).

Of 40 SNPs previously associated with type 2 diabetes, 19 (48%) introduce or remove CpG sites. In 84 human pancreatic islet donors, all 16 analyzed CpG-SNPs showed statistically significant differential DNA methylation (p≤2.3×10⁻⁵). Several CpG-SNPs including rs391300 (SRR), rs5945326 (DUSP9), rs11708067 (ADCY5), rs5015480 (HHEX), rs13266634 (SLC30A8), rs1801214 (WFS1), rs564398 (CDKN2A), and rs2237895 (KCNQ1) were associated with differential gene expression, alternative splicing, or hormone secretion, suggesting DNA methylation-mediated mechanisms linking genetic variants to type 2 diabetes pathogenesis.

This case-control study investigated 25 T2DM-associated SNPs in a multi-ethnic Hawaiian cohort (291 GDM cases, 734 controls) and found ethnicity-specific associations with gestational diabetes. Key findings in Filipinos included rs1113132 (EXT2, OR=1.52, p=0.028), rs1111875 (HHEX, OR=1.5, p=0.047), rs2237892 (KCNQ1, OR=0.49, p<0.001), rs10830963 (MTNR1B, OR=0.63, p=0.025), and rs13266634 (SLC30A8, OR=0.58, p=0.011). In Japanese women, rs4402960 (IGFBP2, OR=0.5, p=0.031) and rs2237892 (KCNQ1, OR=0.5, p=0.03) were significant. Pacific Islanders showed associations with rs10830963 (MTNR1B, OR=0.52, p=0.037) and rs13266634 (SLC30A8, OR=2.43, p=0.03). No SNPs showed consistent associations across all three ethnic groups.

Association analysis of 31 GWAS-confirmed type 2 diabetes SNPs in 3,089 Indian sib pairs (2,528 for quantitative traits, 561 for diabetes) identified significant associations with intermediate traits: CDKAL1 rs7756992, TCF7L2 rs7903146 and rs12255372 with fasting glucose (β=0.009-0.01, p≤0.01); ADAM30 rs2641348, NOTCH2 rs10923931, TCF-2/HNF1B rs757210, and CDKN2A/B rs10811661 with fasting insulin and HOMA-IR (β=±0.05-0.09, p≤0.05); and THADA rs7578597 with type 2 diabetes (OR 1.5, p=0.03).

This association study identified rs10811661 near CDKN2A/B on chromosome 9p21, a type 2 diabetes risk SNP, as significantly associated with diabetic nephropathy in 2,963 type 1 diabetes patients (OR 1.33, p=0.00045). The association was replicated in meta-analysis across four cohorts (n>5,000; OR 1.15, p=0.011) and was particularly strong for end-stage renal disease (OR 1.35, p=0.00038). The SNP was also associated with severe retinopathy but not cardiovascular disease.

Population-based study of 6,733 non-diabetic Finnish men examining associations between 19 confirmed type 2 diabetes risk loci and tissue-specific insulin resistance indices. Type 2 diabetes risk SNPs in KCNJ11 (rs5219) and HHEX (rs1111875) showed significant associations with lower liver insulin resistance (p<0.0013 and p=5.4×10⁻⁵, respectively), while the Pro12 allele of PPARG2 (rs1801282) was significantly associated with higher adipocyte insulin resistance (p=6.2×10⁻⁵).

This association study of 4,213 Danish individuals examined 25 type 2 diabetes risk variants and their association with birthweight. The study found that type 2 diabetes risk alleles near ADCY5 (rs11708067, β = -33 g, p = 0.004), CDKAL1 (rs7756992, β = -22 g, p = 0.04), and HHEX-IDE (rs1111875, β = -16 g in meta-analysis, p = 8×10⁻⁵, n = 25,164) were associated with reduced birthweight, supporting the fetal insulin hypothesis. Meta-analyses confirmed these associations and showed no strong general effect on birthweight from the 25 common type 2 diabetes risk alleles combined.

In 1,412 non-diabetic German participants, carriers of higher cumulative loads of type 2 diabetes risk alleles (rs7903146 in TCF7L2, rs7754840 in CDKAL1, rs7923837 in HHEX, rs13266634 in SLC30A8) showed significantly accelerated age-dependent decline in insulin secretion and impaired proinsulin conversion. Individuals with 5-8 risk alleles exhibited a ~13-18% reduction in insulin secretion compared to carriers of ≤3 alleles, with effects particularly pronounced in obese participants.

This association study of 1,578 German non-diabetic individuals at increased type 2 diabetes risk found that the WFS1 rs10010131 variant was associated with reduced oral glucose tolerance test (OGTT)-derived insulin secretion (p=0.03). Importantly, glucose stimulation via intravenous injection did not reduce insulin secretion in carriers, indicating the variant specifically impairs glucagon-like peptide-1 (GLP-1)-induced insulin secretion (first phase p=0.007, second phase p=0.04). The genetic effect was independent of insulin sensitivity and the TCF7L2 locus.

This case-control study in 869 Korean women with gestational diabetes mellitus (GDM) and 632 non-diabetic controls examined whether type 2 diabetes-associated genetic variants discovered in recent GWAS are also associated with GDM. Multiple variants showed significant associations with GDM, including rs7756992 and rs7754840 in CDKAL1 (OR 1.55, p=4.17×10⁻⁹), rs10811661 in CDKN2A-CDKN2B (OR 1.49, p=1.05×10⁻⁷), variants in HHEX, rs4402960 in IGF2BP2 (OR 1.18, p=0.03), rs13266634 in SLC30A8 (OR 1.24, p=0.005), and rs7903146 in TCF7L2 (OR 1.58, p=0.038).

The D.E.S.I.R. prospective cohort study (N=4,707) validated 22 SNPs from genome-wide association studies for type 2 diabetes effects on glucose homeostasis. Risk alleles in SLC30A8 (rs13266634, P=0.0003), NGN3 (rs10823406, P=0.01), and MMP26 (rs2499953, P=0.04) were associated with elevated fasting glucose, while CDKAL1 variants (rs7756992, P=0.003) showed reduced fasting insulin. However, associations with type 2 diabetes incidence were modest (HRs ranging 1.25-2.03), and only SLC30A8 remained significant after Bonferroni correction for HOMA-B.

This candidate gene study of 1,065 German participants investigated seven type 2 diabetes-associated SNPs and their relationship with proinsulin processing. Risk alleles in TCF7L2 (rs7903146), CDKAL1 (rs7754840), and SLC30A8 (rs13266634) significantly impaired proinsulin to insulin conversion (p<0.05), while variants in HHEX showed impaired insulin secretion without affecting proinsulin conversion, demonstrating that these two aspects of beta cell dysfunction are independently regulated.

This comprehensive review article traces the evolution of pharmacogenetics from single-gene analysis to whole-genome approaches. It discusses validated pharmacogenetic biomarkers with clinical impact including CYP2D6, CYP2C9, CYP2C19, TPMT, DPD, VKORC1, UGT1A1, and ADRB1/ADRB2, providing examples of how genetic variants affect drug metabolism and response. The paper emphasizes the importance of integrating pharmacogenetic information into clinical practice and drug development.

This prospective study of 16,143 individuals from the Malmö Preventive Project (mean follow-up 23 years) investigated whether genetic variants in 26 genes previously associated with type 2 diabetes or metabolic syndrome components could predict future development of metabolic syndrome. Polymorphisms in TCF7L2 (rs7903146, OR 1.10, p=0.00097), FTO (rs9939609, OR 1.08, p=0.0065), WFS1 (rs10010131, OR 1.07, p=0.0078), and IGF2BP2 (rs4402960, OR 1.07, p=0.021) predicted metabolic syndrome development, with TCF7L2, WFS1, and IGF2BP2 acting through hyperglycemia and FTO through obesity. A composite genotype score of 17 polymorphisms predicted metabolic syndrome risk (OR 1.04, p<0.00001), with carriers of ≥19 risk alleles having 51% increased risk compared to carriers of ≤12 alleles.

This case-control association study in 864 Japanese type 2 diabetes patients and 864 controls confirmed that three SNPs in HHEX (rs5015480 OR=1.46, rs7923837 OR=1.40, rs1111875 OR=1.30) were significantly associated with type 2 diabetes across ethnic groups. SNPs in FTO, CDKAL1, CDKN2B, and SLC30A8 showed nominal associations, while several SNPs were associated with impaired pancreatic beta cell function measured by HOMA-beta index.