Peripheral Blood Transcriptomic Signatures of Fasting Glucose and Insulin Concentrations.

Diabetes
Authors
Abstract

Genome-wide association studies (GWAS) have successfully identified genetic loci associated with glycemic traits. However, characterizing the functional significance of these loci has proven challenging. We sought to gain insights into the regulation of fasting insulin and fasting glucose through the use of gene expression microarray data from peripheral blood samples of participants without diabetes in the Framingham Heart Study (FHS) (n = 5,056), the Rotterdam Study (RS) (n = 723), and the InCHIANTI Study (Invecchiare in Chianti) (n = 595). Using a false discovery rate q 0.05, we identified three transcripts associated with fasting glucose and 433 transcripts associated with fasting insulin levels after adjusting for age, sex, technical covariates, and complete blood cell counts. Among the findings, circulating IGF2BP2 transcript levels were positively associated with fasting insulin in both the FHS and RS. Using 1000 Genomes-imputed genotype data, we identified 47,587 cis-expression quantitative trait loci (eQTL) and 6,695 trans-eQTL associated with the 433 significant insulin-associated transcripts. Of note, we identified a trans-eQTL (rs592423), where the A allele was associated with higher IGF2BP2 levels and with fasting insulin in an independent genetic meta-analysis comprised of 50,823 individuals. We conclude that integration of genomic and transcriptomic data implicate circulating IGF2BP2 mRNA levels associated with glucose and insulin homeostasis.

Year of Publication
2016
Journal
Diabetes
Volume
65
Issue
12
Pages
3794-3804
Date Published
2016 Dec
ISSN
1939-327X
DOI
10.2337/db16-0470
PubMed ID
27625022
PubMed Central ID
PMC5127245
Links
Grant list
R01 DK078616 / DK / NIDDK NIH HHS / United States
R01 MD009164 / MD / NIMHD NIH HHS / United States
K01 AG000947 / AG / NIA NIH HHS / United States
Z01 AG000185 / AG / NIA NIH HHS / United States
K24 DK080140 / DK / NIDDK NIH HHS / United States
U01 DK078616 / DK / NIDDK NIH HHS / United States
N01HC25195 / HL / NHLBI NIH HHS / United States