The frequency of Trp64Arg polymorphism of the β3-adrenergic receptor gene in healthy and obese Hungarian children and its association with cardiovascular risk factors

Objective: To estimate the frequency of Arg64 allele of the beta(3)-adrenergic receptor (3-BAR) gene in healthy ( H) and obese (O) Hungarian children, and to look for possible associations between this polymorphism and some clinical and metabolic characteristics of obese children. Patients/methods: In all, 147 healthy ( male: 68) and 295 obese ( male: 168) children were examined. The average age of the children in the two groups was 12.4 +/- 1.7 vs 12.6 +/- 3.2, respectively. Exon 1 of 3-BAR was amplified by polymerase chain reaction and the fragments were digested with BstN1. In obese children, oral glucose tolerance test was carried out and blood pressure ( BP) was checked. Results: The frequency of Trp64Arg polymorphism in normal and obese Hungarian children was similar ( H vs O: n = 14/ 9.5% vs n = 35/ 11.8%). Obese children carrying the Arg64 allele ( n = 35, male: 23) were compared to randomly chosen, obese children without the Arg64 allele ( n = 35, male: 20). A significant difference was found between the body weight (81.2 +/- 23.2 vs 75.6 +/- 17.7 kg; mean7 +/-. d.; P<0.01), body fat (38.8 +/- 3.9 vs 36.5 +/- 2.3%; mean +/- s.d.; P<0.05), mean fasting insulin levels (31.4 +/- 16.7 vs 16.9 +/-7.6 mu IU/ ml; P<0.001) and mean systolic BP values (125.2 +/- 10.1 vs 114.5 +/- 8.3 mmHg; P<0.001) of the two obese groups. Conclusions: The frequency of Trp64Arg polymorphism was similar in Hungary as compared to other European countries. Although the prevalence of this polymorphism was similar in H and O children, the presence of Arg64 allele seems to be associated with increased adiposity, elevated systolic BP and higher fasting insulin levels.