Short Report APOA5-1131T>C polymorphism is associated with triglyceride levels in Chinese men L Baum, B Tomlinson and GN Thomas Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, Hong Kong, China Key words: apolipoprotein – genetic – lipid – lipoprotein – SNP Corresponding author: Larry Baum, Department of Medicine and Therapeutics, Chinese University of Hong Kong, Shatin, Hong Kong. Tel.: þ852 26323487; fax: þ852 26373852; e-mail: lwbaum@cuhk.edu.hk Received 5 November 2002, revised and accepted for publication 11 December 2002 Baum L, Tomlinson B, Thomas GN. APOA5-1131T>C polymorphism is associated with triglyceride levels in Chinese men. Clin Genet 2003: 63: 377–379. # Blackwell Munksgaard, 2003 A new apolipoprotein gene, APOA5, was recently discovered near the APOA1/C3/A4 gene cluster. Transgenic mice overexpressing the homologous gene, apoa5, showed reduced plasma triglyceride levels, while knockout mice had greatly increased triglycerides, suggesting that human genetic variants affecting expression of the protein product, APOAV, might affect triglyceride levels. Polymorphisms in the APOA5 gene were indeed found to be associated with triglyceride levels in men, though not in women. We sought to confirm the association of the APOA5-1131T>C polymorphism with triglyceride levels in 167 Chinese men chosen for having either high (1.7mM,n ¼ 82) or low (1.2mM, n ¼ 85) triglycerides. More subjects with high triglycerides had one or two copies of the minor (C) allele of the polymorphism (67%) than did low triglyceride subjects (48%), and combining all subjects showed that those with one or two C alleles had higher triglyceride levels [1.67  2.20 (geometric mean  SD)] than those without (1.22  2.08mM,p ¼ 0.01), confirming the reported effect in a different ethnic group. The C allele is more common in Chinese than in Caucasians (26–40% vs. 8% of alleles), suggesting that the impact of this polymorphism on triglyceride levels in the population and therefore on public health is greater among Chinese. A novel apolipoprotein gene, APOA5, was recently identified near the APOA1/C3/A4 gene cluster on human chromosome 11q23 (1, 2). Overexpression of the homologous gene in trans- genic or virally transfected mice decreased plasma levels of triglycerides by a factor of three, while eliminating expression in knockout mice increased triglyceride levels by a factor of four (1, 3). Three human APOA5 polymorphisms were found to be associated with triglyceride levels in men, though not in women (1). These non-coding single nucleotide polymorphisms (SNPs), located 5 0 to the gene (-1131T>C), in intron 3 (IVS3þ476G>A), and in the 3 0 untrans- lated region (1259T>C), display similar allele fre- quencies and associations with triglyceride levels, and the SNPs were found to be in linkage dis- equilibrium with each other (1). The association of APOA5 variants with triglyceride levels was confirmed in several recent reports (4–7). In order to confirm the effect of APOA5 genetic var- iation on triglyceride levels, we genotyped the -1131 polymorphism [called SNP3 in (1); Reference SNP Id no. 662799] in 167 Chinese men whose lipid profiles had been previously analyzed. Materials and methods All subjects gave written, informed consent. They were of Han Chinese origin and lived in Hong Kong. Patients were recruited after referral to the Prince of Wales Hospital outpatient medical clinics for the treatment of hypertension, diabetes, or dyslipidemia. Healthy control subjects were recruited from hospital staff and their friends. Subjects were examined in previous studies (8). Clin Genet 2003: 63: 377–379 Copyright # Blackwell Munksgaard 2003 Printed in Denmark. All rights reserved CLINICAL GENETICS ISSN 0009-9163 377