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Association of common JAK2 variants with body fat, insulin sensitivity and lipid profile

Dongliang Ge1, Sakina B Gooljar, Theodosios Kyriakou

  • 1Center for Population Genomics and Pharmacogenetics, Duke University, Durham, NC, USA.

Obesity (Silver Spring, Md.)
|February 2, 2008
PubMed

Insights

Common variations in the Janus kinase 2 (JAK2) gene were not associated with body fat or serum lipid profiles in this study. Researchers found no significant links between JAK2 single-nucleotide polymorphisms (SNPs) and these health markers.

Area of Science:

  • Genetics and Molecular Biology
  • Metabolic Diseases
  • Obesity Research

Background:

  • Leptin signaling involves the Janus kinase 2-signal transducer and activator of transcription-3 (JAK2-STAT3) pathway.
  • JAK2 plays a role in insulin signaling and cellular lipid transport via apolipoprotein A-1 (apoA-I).
  • Common genetic variations in JAK2 could potentially influence body fat, insulin sensitivity, and lipid profiles.

Purpose of the Study:

  • To investigate the association between common variations in the JAK2 gene and body fat, insulin sensitivity, and serum lipid profiles.
  • To determine if specific single-nucleotide polymorphisms (SNPs) in JAK2 correlate with metabolic phenotypes in a general population.

Main Methods:

  • Genotyped ten tagging single-nucleotide polymorphisms (SNPs) in the JAK2 gene.
  • Analyzed data from 2,760 white female twin subjects.
  • Assessed associations between JAK2 SNPs and quantitative traits including body fat measurements and serum lipid levels.

Main Results:

  • One SNP (rs7849191) showed a nominal association with higher central body fat and waist circumference.
  • Another SNP (rs3780378) was nominally associated with altered serum apolipoprotein A (apoA), total cholesterol, LDL cholesterol, and triglycerides.
  • No associations remained statistically significant after adjusting for multiple testing.

Conclusions:

  • Despite JAK2's known roles in leptin and insulin signaling, common genetic variations were not definitively associated with body fat or lipid profiles in this cohort.
  • Further research may be needed to explore the complex genetic underpinnings of these metabolic traits.

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