Gene: TBC1D4

Alternate names for this Gene: AS160|NIDDM5

Gene Summary: This gene is a member of the Tre-2/BUB2/CDC16 domain family. The protein encoded by this gene is a Rab-GTPase-activating protein, and contains two phopshotyrosine-binding domains (PTB1 and PTB2), a calmodulin-binding domain (CBD), a Rab-GTPase domain, and multiple AKT phosphomotifs. This protein is thought to play an important role in glucose homeostasis by regulating the insulin-dependent trafficking of the glucose transporter 4 (GLUT4), important for removing glucose from the bloodstream into skeletal muscle and fat tissues. Reduced expression of this gene results in an increase in GLUT4 levels at the plasma membrane, suggesting that this protein is important in intracellular retention of GLUT4 under basal conditions. When exposed to insulin, this protein is phosphorylated, dissociates from GLUT4 vesicles, resulting in increased GLUT4 at the cell surface, and enhanced glucose transport. Phosphorylation of this protein by AKT is required for proper translocation of GLUT4 to the cell surface. Individuals homozygous for a mutation in this gene are at higher risk for type 2 diabetes and have higher levels of circulating glucose and insulin levels after glucose ingestion. Alternative splicing results in multiple transcript variants encoding different isoforms.

Gene is located in Chromosome: 13

Location in Chromosome : 13q22.2

Description of this Gene: TBC1 domain family member 4

Type of Gene: protein-coding

rs9565164 in TBC1D4 gene and Diabetic Retinopathy PMID 23562823 2013 Genome-wide association study in a Chinese population with diabetic retinopathy.

rs9573563 in TBC1D4 gene and Finding of Mean Corpuscular Hemoglobin PMID 29403010 2018 Genetic analysis of quantitative traits in the Japanese population links cell types to complex human diseases.

rs7330796 in TBC1D4 gene and Glucose tolerance test PMID 25043022 2014 A common Greenlandic TBC1D4 variant confers muscle insulin resistance and type 2 diabetes.

rs9573563 in TBC1D4 gene and Mean Corpuscular Volume (result) PMID 29403010 2018 Genetic analysis of quantitative traits in the Japanese population links cell types to complex human diseases.

PMID 27863252 2016 The Allelic Landscape of Human Blood Cell Trait Variation and Links to Common Complex Disease.

rs9573569 in TBC1D4 gene and Platelet mean volume determination (procedure) PMID 27863252 2016 The Allelic Landscape of Human Blood Cell Trait Variation and Links to Common Complex Disease.

rs9573567 in TBC1D4 gene and Red Blood Cell Count measurement PMID 29403010 2018 Genetic analysis of quantitative traits in the Japanese population links cell types to complex human diseases.

PMID 27863252 2016 The Allelic Landscape of Human Blood Cell Trait Variation and Links to Common Complex Disease.

PMID 30595370 2019 Leveraging Polygenic Functional Enrichment to Improve GWAS Power.