INTRODUCTION: Gout and hyperuricaemia attributed to genetic and lifestyle factors have been associated with several chronic diseases. This study aimed to determine the association and interaction effects between vascular endothelial growth factor receptor-2 (VEGFR-2) gene polymorphisms (rs1870377 and rs2071559) and dietary patterns on blood uric acid in Malay and Indian adults.
METHODS: Dietary intakes of 153 Malays and 177 Indians were obtained using a food frequency questionnaire for the construction of dietary patterns using factor analysis. Genotyping of rs1870377 and rs2071559 was performed by real-time PCR using TaqMan probes. Anthropometric measurements, body mass index (BMI) and blood pressure and biomarkers, uric acid, glycated haemoglobin A1c (HbA1c), and blood lipids were determined.
RESULTS: There were significant differences in the mean values for HbA1c (41±-12 vs 45±-8 mmol/mol, p<0.001) and blood lipids levels (p<0.05) between Malays and Indians. Significant correlations were obtained between uric acid with selected blood lipids (p<0.05) and BMI in Malays (r=0.362, p<0.001) and Indians (r=0.212, p<0.01). Four dietary patterns were extracted from dietary intakes of all subjects: ‘Vegetables diet’; ‘Fruits diet’ (FD); ‘Animal protein and rice diet’; and ‘Fast foods and preserved foods diet’. There were no significant associations between dietary patterns (p=0.054-0.609) and VEGFR-2 gene polymorphisms (p=0.348-0.778) with uric acid. In Malay subjects, the interaction of rs2071559 and FD had a borderline effect (p=0.05) on blood uric acid after adjusting for potential confounders.
CONCLUSION: The associations and gene-diet interactions involving VEGFR-2 gene polymorphisms and FD on uric acid provide new information on gout and hyperuricaemia risks in Malays.
Keywords: Gene-diet interaction, VEGFR-2 gene polymorphisms, dietary pattern, uric acid, Malaysians
AIM: The main objective of this study is to elucidate the clinical significance of the SLC2A9/GLUT9 rs11722228 polymorphism among male gout patients.
METHOD: We consecutively recruited all newly diagnosed male gout patients who were treatment-naive from the rheumatology outpatient clinics of two Malaysian hospitals. Age-matched healthy male adults were employed as controls. All subjects were tested for the SLC2A9/GLUT9 rs11722228 genotypes, serum uric acid (SUA), urine uric acid and creatinine levels. All gout subjects were examined for the presence of tophi and sonographically screened for renal calculi.
RESULTS: A total of 73 male gout patients and 73 age-matched healthy male adults were recruited in this study. The genotypic frequencies of SLC2A9/GLUT9 rs1172228 did not differ significantly between the gout cases and the healthy controls. The gout subjects with the CC genotype had significantly higher SUA levels (P = 0.002), family history of gout (P < 0.050) and the occurrence of renal calculi (P = 0.026). The SUA-adjusted odds ratios (OR) of the occurrence of renal calculi in the CC genotype (OR = 1 [reference]) was significantly higher than the CT genotype (OR = 0.338, 95%CI: 0.141-0.813) and the TT genotype (OR = 0.271, 95%CI: 0.086-0.854).
CONCLUSIONS: The genotypic distribution of SLC2A9/GLUT9 rs1172228 in male gout patients did not differ significantly from that of healthy male controls. However, the CC genotype in gout had significant associations with higher levels of SUA, renal calculi and a positive family history of gout.
Study site: Rheumatology clinic, Tuanku Jaafar Hospital, Malaysia and Putrajaya Hospital, Malaysia