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

Associations between TUBB-WWOX SNPs, their haplotypes, gene-gene, and gene-environment interactions and dyslipidemia

In this study, we investigated associations between single nucleotide polymorphisms (SNPs) in the tubulin beta class I (TUBB) and WW domain-containing oxidoreductase (WWOX) genes, gene-gene interactions, and gene-environment interactions and dyslipidemia in the Chinese Maonan ethnic group. Four SNPs (rs3132584, rs3130685, rs2222896, and rs2548861) were genotyped in unrelated subjects with normal lipid levels (864) or dyslipidemia (1129). While 5.0% of Maonan subjects carried the rs3132584TT genotype, none of the Chinese Han in Beijing subjects did. Allele and genotype frequencies differed between the normal and dyslipidemia groups for three SNPs (rs3132584, rs3130685, and rs2222896). rs2222896G allele carriers in the normal group had higher low-density lipoprotein cholesterol and lower high-density lipoprotein cholesterol levels. The rs3132584GG, rs3130685CC+TT, and rs2222896GG genotypes as well as the rs2222896G-rs2548861G and rs2222896G-rs2548861T haplotypes were associated with an elevated risk of dyslipidemia; the rs2222896A-rs2548861T and rs2222896A-rs2548861G haplotypes were associated with a reduced risk of dyslipidemia. Among the thirteen TUBB-WWOX interaction types identified, rs3132584T-rs3130685T-rs2222896G-rs2548861T increased the risk of dyslipidemia 1.371-fold. Fourteen two- to four-locus optimal interactive models for SNP-SNP, haplotype-haplotype, gene-gene, and gene-environment interactions exhibited synergistic or contrasting effects on dyslipidemia. Finally, the interaction between rs3132584 and rs2222896 increased the risk of dyslipidemia 2.548-fold and predicted hypertension.

Associations of PRKN-PACRG SNPs and G × G and G × E interactions with the risk of hyperlipidaemia

This research aimed to assess the associations of 7 parkin RBR E3 ubiquitin protein ligase (PRKN) and 4 parkin coregulated gene (PACRG) single-nucleotide polymorphisms (SNPs), their haplotypes, gene-gene (G × G) and gene-environment (G × E) interactions with hyperlipidaemia in the Chinese Maonan minority. The genotypes of the 11 SNPs in 912 normal and 736 hyperlipidaemic subjects were detected with next-generation sequencing technology. The genotypic and allelic frequencies of the rs1105056, rs10755582, rs2155510, rs9365344, rs11966842, rs6904305 and rs11966948 SNPs were different between the normal and hyperlipidaemic groups (P < 0.05-0.001). Correlations between the above 7 SNPs and blood lipid levels were also observed (P < 0.0045-0.001, P < 0.0045 was considered statistically significant after Bonferroni correction). Strong linkage disequilibrium was found among the 11 SNPs (r2 = 0.01-0.64). The most common haplotypes were PRKN C-G-T-G-T-T-C (> 15%) and PACRG A-T-A-T (> 40%). The PRKN C-G-C-A-T-T-C and PRKN-PACRG C-G-T-G-T-T-C-A-T-A-T haplotypes were associated with an increased risk of hyperlipidaemia, whereas the PRKN-PACRG C-G-T-G-C-T-C-A-T-C-T and C-G-T-G-T-T-C-A-T-C-T haplotypes provided a protective effect. Association analysis based on the haplotypes and G × G interaction could improve the power to detect the risk of hyperlipidaemia over the analysis of any one SNP alone. The differences in serum lipid parameters between the hyperlipidaemic and normal groups might partly be due to the effects of the PRKN-PACRG SNPs and their haplotypes.

SYNE1-QK1 SNPs, G × G and G × E interactions on the risk of hyperlipidaemia

This study aimed to assess the relationship of 3 spectrin repeat containing nuclear envelope protein 1 (SYNE1) and 4 KH domain containing RNA binding (QK1) single nucleotide polymorphisms (SNPs), their haplotypes, gene‐gene (G × G), gene‐environment (G × E) interactions and hypercholesterolaemia (HCH) and hypertriglyceridaemia (HTG) in the Chinese Maonan minority. The genetic make‐up of the SYNE1‐QK1 SNPs in 1932 unrelated subjects (normal, 641; HCH, 649; and HTG, 642) was obtained by next‐generation sequencing technologies. The genotypic frequencies of following SNPs were suggestively distinctive between the control and HCH groups (rs2623963, rs7745725, rs9459317, rs16897566), or between the control and HTG groups (rs2623963, rs1358317, rs7745725, rs1923608, rs16897566 SNPs; P < .05, respectively). Multiple‐locus linkage disequilibrium analysis indicated that the identified SNPs were not inherited independently. Several haplotypes and gene‐gene interaction haplotypes among the detected SNPs may be related with an increased morbidity of HCH (C‐G‐A, C‐G‐G and C‐G‐G‐T‐C‐A‐T) and HTG (C‐G‐G, G‐T‐G‐C, C‐G‐G‐G‐T‐G‐C and C‐G‐G‐T‐C‐A‐T), whereas others may be related with an decreased risk of HCH (G‐A‐A, G‐C‐A‐T, C‐A‐A‐T‐C‐A‐T and G‐A‐A‐G‐C‐A‐T) and HTG (G‐A‐A, G‐C‐A‐T, C‐A‐A‐T‐C‐A‐T and G‐A‐A‐G‐C‐A‐T). The association evaluation based on haplotypes and gene‐gene interactions could improve the power of detecting the risk of dyslipidaemia than anyone of SNP alone. There was significant three‐locus model involving SNP‐SNP, haplotype‐haplotype/environment and G × G interactions (P < .05‐0.001) that were detected by GMDR in HCH and HTG groups. Different interactions between genetic and environmental factors would produce different redundancy or synergy effects on the morbidity of HCH and/or HTG.

EHBP1 SNPs, Their Haplotypes, and Gene-Environment Interactive Effects on Serum Lipid Levels

The associations between single nucleotide polymorphisms (SNPs) rs2710642 and rs10496099 and their effect on the EH domain-binding protein 1 (EHBP1) gene and serum lipid profiles remain uncertain. This study was performed to investigate the two EHBP1 SNPs in Han and Maonan populations, including their association, haplotypes, and effects on serum lipid levels. Two EHBP1 SNPs in 564 Han and 796 Maonan participants were genotyped by high-throughput sequencing, and then the genotype and haplotype distributions of two EHBP1 SNPs were analyzed. Moreover, risk factors and their effects on serum lipid levels were analyzed using multivariable linear regression and logistic regression analyses. In Han and Maonan populations, a significant difference was found in the allelic and genotypic frequencies of the EHBP1 rs2710642 and rs10496099 SNPs and the alternate alleles of rs2710642A and rs10496099C might be potentially beneficial for healthy lipid levels. Medium linkage disequilibrium between the two SNPs was noted in each ethnic group, and four main haplotypes were detected. The rs2710642G-rs10496099C haplotype was associated with high triglycerides (TGs) and low high-density lipoprotein cholesterol, and the rs2710642A-rs10496099C haplotype was associated with low TGs and high apolipoprotein A1. The rs2710642G-rs10496099C haplotype was a high-risk factor for hyperlipidemia, and it interacted with smoking, fasting blood glucose, and hypertension to increase but with the female factor to decrease the prevalence of hyperlipidemia in Han individuals. The EHBP1 rs2710642 and rs10496099 SNPs and gene-environment interactions were associated with serum lipid profiles and hyperlipidemia, which is of ethnic specificity to our study populations.

Correlation Between the APOB rs1042034 SNP and Blood Lipid Characteristics of 2 Ethnic Groups in China

The apolipoprotein (Apo) B gene (APOB) is a susceptible gene for dyslipidemia. The purpose of this investigation was to explore the relationship between the APOB rs1042034 single-nucleotide polymorphism (SNP) and serum lipid levels in the Maonan and Han populations. A total of 598 Maonan participants and 609 Han participants were genotyped by polymerase chain reaction and restriction fragment length polymorphism, and the genotypes were also verified by sequencing. There were no differences in genotype and allele frequencies between the 2 ethnic groups or between males and females. The levels of triglyceride (TG) in Maonans were higher and high-density lipoprotein cholesterol was lower in the A allele carriers than the A allele noncarriers; the A allele carriers in Hans had higher TG levels and lower ApoA1/ApoB ratio than the A allele noncarriers (P < .05 for all). Subgroup analysis showed that the A allele carriers in Maonan females had higher TG levels and the A allele carriers in Han females had higher TG levels and lower ApoA1/ApoB ratio than the A allele noncarriers (P < .05 for all). In our study populations, there may be ethnicity- and/or sex-specific associations between the APOB rs1042034 SNP and serum lipid levels.

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

Introduction

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.

Methods

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.

Results

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).

Conclusions

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.