Abstract
Distinct tissue-specific mechanisms mediate insulin action in fasting and postprandial states. Previous genetic studies have largely focused on insulin resistance in the fasting state, where hepatic insulin action dominates. Here we studied genetic variants influencing insulin levels measured 2 h after a glucose challenge in >55,000 participants from three ancestry groups. We identified ten new loci (P < 5 × 10−8) not previously associated with postchallenge insulin resistance, eight of which were shown to share their genetic architecture with type 2 diabetes in colocalization analyses. We investigated candidate genes at a subset of associated loci in cultured cells and identified nine candidate genes newly implicated in the expression or trafficking of GLUT4, the key glucose transporter in postprandial glucose uptake in muscle and fat. By focusing on postprandial insulin resistance, we highlighted the mechanisms of action at type 2 diabetes loci that are not adequately captured by studies of fasting glycemic traits.
Originalsprog | Engelsk |
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Tidsskrift | Nature Genetics |
Vol/bind | 55 |
Udgave nummer | 6 |
Sider (fra-til) | 973-983 |
ISSN | 1061-4036 |
DOI | |
Status | Udgivet - jun. 2023 |
Bibliografisk note
Funding Information:All data used in genetic risk score association analyses are available from the UK Biobank upon application ( https://www.ukbiobank.ac.uk ). All analyses in the UK Biobank in this manuscript were conducted under application 44448. Further details about the RISC study and data availability can be found here: http://www.egir.org/egirrisc/ . The Genotype-Tissue Expression (GTEx) Project was supported by the Common Fund of the Office of the Director of the National Institutes of Health, and by NCI, NHGRI, NHLBI, NIDA, NIMH and NINDS. The data used for the analyses described in this manuscript can be obtained from the GTEx Portal ( https://www.gtexportal.org/home/ ) and dbGaP accession number phs000424.v8.p2 . Genome regulatory annotations from ENCODE ( https://www.encodeproject.org/ ) and Roadmap Epigenomics Consortium ( https://egg2.wustl.edu/roadmap/web_portal/ ) were explored via UCSC Genome Browser ( http://genome.ucsc.edu ). Published differentiated 3T3-L1 RNA-sequencing data used in this study are available from GEO accession GSE129957 ( https://www.ncbi.nlm.nih.gov/geo/ ). are provided with this paper.
Publisher Copyright:
© 2023, The Author(s), under exclusive licence to Springer Nature America, Inc.