Objectives: Hypertriglyceridaemia has been recognized as an independent risk factor for the development of coronary heart disease. Apolipoprotein A-IV (apo A-IV) plays an important role in the metabolism of TG-rich lipoproteins and HDL. However, the role of the polymorphism of the apo A-IV gene in hyperlipidaemia remains to be fully determined. The impact of the genetic variant in the apolipoprotein A-IV gene on lipid risk factor profiles for coronary heart disease was examined in Chinese patients with type-IV hyperlipoproteinaemia (HTG) and in healthy control individuals.
Methods: We genotyped five polymorphisms in the apo A-IV gene (codon 9, codon 347, codon 360, 3'end VNTR and Msp I sites) by direct sequencing or RFLP analysis in a Chinese population.
Results: The genotype frequencies in our results were significantly different from those reported in Caucasians. The polymorphic sites of codon 347 and codon 360, that have been widely studied in Western populations, were not observed in our population. The frequency of the G allele at codon 9 in HTG subjects was higher than that in healthy controls (P < 0.05). Serum apolipoprotein A-I (apo A-I), triglyceride (TG) and low-density lipoprotein cholesterol (LDLC) levels were affected by genotypes of codon 9, Msp I and VNTR polymorphisms, respectively, with some sex-specific effects in the control or HTG group.
Conclusion: These results suggest that codon 9, Msp I and VNTR polymorphisms in the apo A-IV gene are associated with type-IV hyperlipoproteinaemia in a Chinese population.