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Catechol-O-methyltransferase association with hemoglobin A1c.

Kathryn T Hall1,2, Kathleen A Jablonski3, Ling Chen4

  • 1Division of Preventive Medicine, Brigham and Women's Hospital, Boston, MA, USA.

Metabolism: Clinical and Experimental
|June 11, 2016
PubMed
Summary

Genetic variations in catechol-O-methyltransferase (COMT) were linked to lower HbA1c and reduced risk of type 2 diabetes. These findings align with COMT

Keywords:
COMTDiabetes Prevention Program (DPP)Hemoglobin A1CType 2 diabetesWomen's Health Study (WHS)

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Area of Science:

  • Genetics and Genomics
  • Metabolic Disorders
  • Cardiovascular Disease

Background:

  • Catecholamines influence metabolic factors like blood pressure, insulin sensitivity, and blood glucose.
  • Genetic variations in catechol-O-methyltransferase (COMT), an enzyme degrading catecholamines, are linked to cardiometabolic risk and cardiovascular disease (CVD).
  • Understanding COMT's role in glycemic regulation and type 2 diabetes is crucial for metabolic health research.

Purpose of the Study:

  • To investigate the association between COMT gene polymorphisms and glycemic control (HbA1c).
  • To examine the relationship between COMT variations and susceptibility to type 2 diabetes.
  • To explore COMT's potential role in modifying responses to type 2 diabetes treatments like metformin.

Main Methods:

  • Analyzed COMT polymorphisms (rs4680, rs4818, rs4633) in large cohorts: Women's Genome Health Study (WGHS), Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC), DIAbetes Genetics Replication And Meta-analysis consortium (DIAGRAM), and Diabetes Prevention Program (DPP).
  • Assessed associations with baseline HbA1c and type 2 diabetes incidence.
  • Examined treatment interactions, specifically with metformin and aspirin, in the DPP cohort.

Main Results:

  • The high-activity G-allele of COMT rs4680 was associated with lower HbA1c in WGHS and showed a borderline significant trend in MAGIC.
  • Combined COMT per val allele effects demonstrated a significant association with reduced type 2 diabetes risk across WGHS, DIAGRAM, and DPP cohorts.
  • In the DPP, the rs4680 val allele showed a borderline association with lower type 2 diabetes incidence in participants randomized to metformin.

Conclusions:

  • The high-activity G-allele of COMT rs4680 is associated with improved glycemic control (lower HbA1c) and offers modest protection against type 2 diabetes.
  • The observed directionality of COMT associations aligns with previous findings related to cardiometabolic risk factors and CVD.
  • COMT genetic variations may influence type 2 diabetes susceptibility and potentially treatment response, warranting further investigation.