Objective: To determine the relationship between two common apoA-IV variants (Thr347-->Ser; Gln360-->His), and body mass index (BMI) and percentage body fat.
Design: Cross-sectional study.
Subjects: Eight-hundred and forty-eight subjects screened for participation in ongoing clinical studies.
Measurements: ApoA-IV genotype, body mass index, waist-to-hip ratio and percentage body fat by bioelectric impedance.
Results: Participants had an average age of 41+/-12 y and an average BMI of 28.2+/-5.5 kg/m2. Individuals homozygous for the Ser347 allele had higher BMI (32.3+/-6.6 vs 28.6+/-5.3 kg/m2; P<0.01) and percentage body fat (36.9+/-7.8 vs 31.0+/-9.6%; P<0.05) compared with individuals homozygous for Thr347. In contrast, the presence of at least one copy of the His360 allele was associated with lower BMI (27.2+/-5.0 vs 28.4+/-5.6 kg/m2; P<0.05) and percentage body fat (28.6+/-8.2 vs 30.7+/-9.1%; P<0.05). The genotype effects persisted after normalization of the data for the potential confounding effects of gender, age and race. When grouped by BMI percentile, the frequency of the Ser347/Ser347 genotype increased while the frequency of the His360 allele decreased with increasing BMI.
Conclusions: These data suggest a role for apoA-IV in fat storage or mobilization and that genetic variations in the apoA-IV gene may play a role in the development of obesity.