Associations of a human G protein beta3 subunit dimorphism with insulin resistance and carotid atherosclerosis.

Abstract

BACKGROUND AND PURPOSE:

The C825T dimorphism of the gene encoding the human G protein beta3 subunit (GNB3) is associated with hypertension and obesity. Although these findings suggest an association with insulin resistance and atherosclerosis, this hypothesis has yet been tested only partially.

METHODS:

To investigate this hypothesis, the C825T dimorphism was determined in a population of 932 middle-aged white subjects of middle European (Austrian) origin. Insulin sensitivity was measured with the short insulin tolerance test; intima-media thickness of the carotid artery and morphological plaque burden were measured by ultrasound.

RESULTS:

Insulin sensitivity was found to be significantly lower in carriers of the T allele (3.55+/-1.27 versus 3.92+/-1.30%/min, P=0.012) in the group of male subjects with abdominal body fat distribution (waist-to-hip ratio >0.9). No effect was observed in women or men with a waist-to-hip ratio <0.9. Advanced carotid artery plaques were more frequent (odds ratio, 1.606; 95% confidence interval, 1.002 to 2.575; P=0.04) in carriers of the T allele regardless of sex. No effect was observed with regard to carotid artery intima-media thickness.

CONCLUSIONS:

In summary, our results demonstrate that the GNB3 825T allele is associated with reduced insulin sensitivity in men with abdominal fat distribution and with more advanced carotid atherosclerosis in middle-aged white men and women.

• Authors: Thomas C Wascher, Bernhard Paulweber, Liliane Malaimare, Andreas Stadlmayr, Bernhard Iglseder, Isabella Schmoelzer, Wilfried Renner
• Journal: Stroke (Stroke) Vol. 34 Issue 3 Pg. 605-9 (Mar 2003) ISSN: 1524-4628 [Electronic] United States
• PMID: 12624279 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Protein Subunits
• Heterotrimeric GTP-Binding Proteins

Topics

• Adult
• Aged
• Alleles
• Austria (epidemiology)
• Blood Pressure (genetics)
• Body Constitution (genetics)
• Carotid Arteries (diagnostic imaging)
• Carotid Artery Diseases (diagnostic imaging, epidemiology, genetics)
• Cohort Studies
• Comorbidity
• DNA Mutational Analysis
• Female
• Gene Frequency
• Heterotrimeric GTP-Binding Proteins (genetics)
• Humans
• Hypertension (epidemiology)
• Insulin Resistance (genetics)
• Male
• Middle Aged
• Polymorphism, Genetic
• Prevalence
• Protein Subunits (genetics)
• Ultrasonography
• White People (genetics)