Association of the Trp64Arg mutation of the beta3-adrenergic receptor with fatty liver and mild glucose intolerance in Japanese subjects.

The prevalence of a mutation of the codon for tryptophan 64 to arginine (Trp64Arg) in the beta3-adrenergic receptor gene was investigated by genotyping 261 Japanese subjects. The allelic frequency of this mutation was 0.18. Subjects with the homozygous W64R mutant alleles had a significantly higher prevalence of fatty liver, BMI, serum gamma-glutamyl transpeptidase, and serum leucine amino transpeptidase levels than those without the mutation. Individuals with this mutation also showed a higher fasting blood glucose level than those without this mutation. However, the prevalence of diabetes mellitus was no different between the three groups. These results suggest a potential association of the Trp64Arg mutation with higher morbidity of fatty liver and mild glucose intolerance.