Common mutations in the lipoprotein lipase gene (LPL): effects on HDL-cholesterol levels in a Chinese Canadian population

Background: favorable lipid profiles including low total serum cholesterol (TC), TC/HDL-cholesterol (HDL-C) ratio and elevated HDL-C levels have been previously reported in Chinese living in China. More recent data, however, suggests a changing trend toward decreased HDL-C and increased TC and LDL cholesterol (LDL-C) in Chinese populations. Environmental factors likely contribute, in part, to these findings. However, genetic factors contributing to lipoprotein metabolism may also play a role in determining the lipid/lipoprotein phenotype observed in Chinese populations. Lipoprotein lipase (LPL) mutations have been associated with altered HDL-C concentrations in Caucasians but have not yet been studied in a large population of Chinese descent. Methods: 1577 Chinese Canadians of Cantonese descent were recruited for a cardiovascular risk factor study. The frequency and effect of three LPL gene polymorphisms [Asp9Asn (D9N, n = 374), Asn291Ser (N291S, n = 321) and Ser447-Ter (S447X, n = 403)] on serum HDL-C concentrations was assessed. All the three polymorphisms have been shown to alter HDL-C levels in different Caucasian populations. Results: lower TC, LDL-C, and TG and higher HDL-C were observed in both male and female Chinese Canadian subjects compared to other population samples. The D9N and N291S LPL polymorphisms were identified in 1/374 (0.3%) and 5/321 (1.6%) subjects, respectively. Carrier frequency of the S447X mutation was (102/403) 25.3%. This S447X polymorphism was observed with higher frequency in males with HDL-C levels in the highest tertile compared with those in the lowest HDL-C tertile (carrier frequencies 37.3 vs. 19.4%) (P = 0.046). Conclusion: in this cohort of Chinese Canadians, the serum lipid profiles were more favorable than what has been reported for Caucasian Canadians. A favorable spectrum of polymorphisms in the LPL gene may mitigate the adverse effects of western lifestyle on plasma lipoproteins in this cohort of Cantonese Canadians. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.