Association between the LIPG polymorphisms and serum lipid levels in the Maonan and Han populations

The Maonan population is a relatively isolated minority in China. Little is known about endothelial lipase gene (LIPG) single nucleotide polymorphisms (SNPs) and serum lipid levels in the Chinese populations. The present study aimed to detect the association of several LIPG SNPs and environmental factors with serum lipid levels in the Chinese Maonan and Han populations.

In total, 773 subjects of Maonan ethnicity and 710 participants of Han ethnicity were randomly selected from our previous stratified randomized samples. Genotypes of the LIPG rs2156552, rs4939883 and rs7241918 SNPs were determined by polymerase chain reaction-restriction fragment length polymorphism, and then confirmed by direct sequencing.

The allelic (rs2156552, rs4939883 and rs7241918) and genotypic (rs2156552 and rs4939883) frequencies were different between the two ethnic groups (p < 0.05-0.01). The minor allele carriers had lower apolipoprotein (Apo)A1/ApoB ratio (rs2156552 and rs7241918), high-density lipoprotein cholesterol (HDL-C) and apolipoprotein (Apo)A1 (rs2156552) levels and higher ApoB levels (rs4939883) in the Han population, and lower HDL-C (rs2156552, rs4939883 and rs7241918) levels in the Maonan minority than the minor allele non-carriers (p < 0.0167 after Bonferroni correction). Subgroup analyses according to sex showed that the minor allele carriers had a lower ApoA1/ApoB ratio (rs2156552 and rs7241918) and higher ApoB levels (rs7241918) in Han males, and lower ApoA1 and HDL-C levels in Maonan females than the minor allele non-carriers (p < 0.0167-0.001).

The present study demonstrates the association between the LIPG polymorphsims and serum lipid levels in the two ethnic groups. These associations might have an ethnic- and or/sex-specificity.