The effect of genetic variability on the correlation between blood glucose and glycated hemoglobin levels.

The disturbing results of recent clinical trials aimed to control cardiovascular risk of diabetes by aggressive control of blood glucose prompted us to analyze the effect of genetic variability of 2 polymorphic enzymes abundant in red blood cells on the correlation between blood glucose and glycated hemoglobin (Hb). Two hundred eighty subjects with type 2 diabetes mellitus were studied. Adenylate kinase locus 1 (AK₁) and acid phosphatase locus 1 were determined. Correlation between blood glucose and glycated Hb was determined for phenotypes of the 2 systems. The correlation between blood glucose and glycated Hb is higher in carriers of AK₁*2 allele than in subjects with AK₁1 phenotype. The highest coefficient is observed in acid phosphatase locus 1 phenotypes with the highest enzymatic activity; and the lowest, in phenotypes with the lowest activity. Effects of sex, blood glucose level, age, age at onset, and duration of disease have been also considered. Our data are in agreement with recent observation in healthy subjects suggesting a role of genetic factors on glycated Hb level. If glycation of structural and functional protein is dependent not only on blood glucose level but also on genetic factors, these factors could have an important role in the susceptibility and clinical course of diabetes.