Variations In Serum Lipids Research Articles

Influence of the rs4238001 Genetic Polymorphism of the SR-B1 Gene on Serum Lipid Levels and Response to Rosuvastatin in Myocardial Infarction Iraqi Patients.

Scavenger receptor type B (SR-BI) is a receptor that binds both native and altered lipoproteins. It was revealed to facilitate utilization of high-density lipoprotein HDL and significantly affect the reverse transport of cholesterol. Therefore, the objectives were to identify the possible role of the genetic variant rs4238001 in patients with myocardial infarction (MI) on serum lipid level, and how this variant could impact the response of rosuvastatin drug. The genotyping of the rs4238001 genetic polymorphism of the SR-B1 gene was performed in 300 participants, including 150 MI patients treated with 20mg/day/4 weeks of rosuvastatin and 150 healthy control using Taq man probes (FAM and VIC) by Real-time PCR technique. The concentrations of the lipid profile were evaluated. The significance of the anthropometric data was revealed in the ejection fraction and smoking status (p < 0.05) between groups. The lipid profile shows either significant differences between control and MI patients (pre-treatment) or between pre-and post-treatment of MI patients (p < 0.05), but not HDL-c (p > 0.05). The minor allele frequency MAF% of the T allele and TT genotype were more frequent in MI patients than in controls (P = 0.173; OR = 3.62; 95% CI = 0.74-17.64). CC genotype was found to be associated with response to rosuvastatin therapy with a change of % (29.08 ± 53.2; p = 0.021). In the Iraqi population, the rs4238001 polymorphism of the SR-B1 gene is associated with variations in serum lipids, and the CC genotype of the SNP is related to higher HDL-C in the lipid-lowering rosuvastatin response.

Risk Analysis and Assessment of Lipid Abnormalities as the Earliest Complication in Newly Diagnosed Diabetic and Non-Diabetic Individuals of a Local Population.

Lipid variations have been frequently observed in global populations that can affect health status. Mainly studies have been conducted on the type 2 diabetic population, but limited data is available on newly diagnosed ones to unravel complications and risk predictors independent of disease progression. This study comprising 244 individuals was carried out to assess the lipid abnormalities in newly diagnosed diabetics and non-diabetics. The clinical and socio-demographic data were collected and analyzed using independent samples t-test and linear regression. Serum lipid variations were observed individually and in combination. The individuals in group I (diabetics with dyslipidemia) revealed elevated levels of low-density lipoprotein and serum triglycerides higher than in group II (non-diabetics with dyslipidemia). The frequency of deranged total cholesterol in group I was observed to be higher than in group II. Independent samples t-test showed a significant mean difference in variables between the two groups. Linear regression analysis showed a significant variable outcome for predictors between high-density lipoprotein (HDL) and physical activity (B= -0.043, 95% CI: -0.80, -0.006) and total cholesterol (TC) with family history (B= -0.062, 95% CI: -0.123, -0.001). The findings conclude that lipid levels deranged independently regardless of type 2 diabetes mellitus and present as an early onset in type 2 diabetes instead of later stage complication. These derangements of lipid levels are an independent risk factor for future cardiovascular pathology.

Serum Lipid Variation in Patients with Dengue Virus Infection and Associated Risks of Cardio Vascular Disorder

Background: Dengue virus (DENV) is a most prevalent arbovirus with about 100 million infections worldwide every year. It is endemic in the subtropical and tropical areas in the world, an emerging public health threat. Serum lipidome is a key player in the immune system response of the patient for the period of dengue fever. This study was aimed to assess the lipids deviations in serum of patients with dengue fever. &#x0D; Materials and Methods: Three For this case-control study blood samples of N=65 dengue patients of age ≥18 year were collected from the Mayo Hospital, Lahore. Whereas samples of 45 healthy individuals were collected from the University of the Punjab, Lahore. Blood samples from subjects were collected to analyze serum lipidome. &#x0D; Results: Significantly (P &lt; 0.001) increased serum triglyceride, total cholesterol, low density lipoprotein, and very low-density lipoprotein while a significant (P &lt; 0.001) reduction in high density lipoprotein was observed in the dengue patient’s serum in contrast to the control.&#x0D; Conclusion: We can conclude that DENV infection can contribute to dyslipidemia with subsequent cardiovascular disorder symptoms. Therefore, patients infected with DENV should monitor their serum lipid profiles to deal with DENV induced effects to the cardiovascular physiology.

Plasma Volume Is an Important Determinant in Assessing Metabolic and Iron Biomarkers in Young Women

Abstract Objectives Plasma volume (PV) variations among individuals can affect the concentration of blood biomarkers but this is not often evaluated in assessing nutritional status. We aimed to assess the association between estimated PV, metabolic and iron biomarkers in young obese and normal weight women. Methods Healthy women aged 18–30 y were recruited for the study (n = 47: 25 obese and 22 normal weight). Fasting venous blood samples were obtained to measure serum lipids, comprehensive metabolic panel, iron biomarkers (serum iron, total iron binding capacity, transferrin saturation (%TS), hemoglobin, ferritin and, hepcidin). PV was estimated using Kaplan-Hakim formula: PV = (1-hematocrit) × [a + (b × weight in kg)] where adjustment factors were a = 864, and b = 47.9. Associations between PV and other biomarkers were assessed using Pearson's correlation. Results As expected, PV was higher in obese (3482 (545) mL) than normal weight women (2268 (250) mL). When all subjects were combined PV was negatively correlated with HDL (r = −0.49, P = 0.001), creatinine (r = −0.48, P = 0.001), sodium (r = −0.31, P = 0.034), calcium (r = −0.30, P = 0.044), albumin (r = −0.46, P = 0.001), serum iron (r = −0.34, P = 0.022), and %TS (r = −0.31, P = 0.036) but positively correlated with triglycerides (r = 0.40, P = 0.005), cholesterol/HDLC ratio(r = 0.55, P &amp;lt; 0.001). In normal weight women, PV was not correlated with any of these biomarkers. However, in obese women, there was a strong correlation of PV with creatinine (r = −0.61, P = 0.001), calcium (r = −0.50, P = 0.012), and albumin (r = −0.43, P = 0.030). Conclusions Our results suggest that differences in PV may account for some variations in serum lipids, creatinine, sodium, calcium, albumin, and iron biomarker concentrations in women. This implies that different cutoffs may be needed for defining deficiencies in obesity after correcting for plasma volume. Funding Sources Doris A. Adams Endowed Chair funds at Iowa State University.

Weight loss and its influence on high-density lipoprotein cholesterol (HDL-C) concentrations: A noble clinical hesitation.

The relationship between obesity, weight loss, and high-density lipoprotein cholesterol (HDL-C) is poorly recognized and understood. Through an emphasis on current studies, in this viewpoint, we provide further scientific and medical considerations on the relationship between weight loss and the management of HDL-C levels. Long-term adherence to a low-calorie diet is a determinant of weight loss, with weight loss and/or normal weight being important clinical conditions to lower risk for the development of cardiometabolic dysregulations and cardiovascular diseases. These benefits appear to be independent of variations in serum lipids and lipoproteins. Indeed, there is a paradoxical link between weight loss and HDL-C levels, which can result in both increases and reductions in the concentrations of this recognized biomarker of cardiovascular health. Care should be exercised in order to avoid overvalued clinical recommendations in the management of HDL-C levels. Further hesitation is needed for health practitioners as well as skepticism surrounding science.

Untargeted lipidomics reveals specific lipid abnormalities in Sjögren's syndrome.

The relationship between serum lipid variations in SS and healthy controls was investigated to identify potential predictive lipid biomarkers. Serum samples from 230 SS patients and 240 healthy controls were collected. The samples were analysed by ultrahigh-performance liquid chromatography coupled with Q Exactive™ spectrometry. Potential lipid biomarkers were screened through orthogonal projection to latent structures discriminant analysis and further evaluated by receiver operating characteristic analysis. A panel of three metabolites [phosphatidylcholine (18:0/22:5), triglyceride (16:0/18:0/18:1) and acylcarnitine (12:0)] was identified as a specific biomarker of SS. The receiver operating characteristic analysis showed that the panel had a sensitivity of 84.3% with a specificity of 74.8% in discriminating patients with SS from healthy controls. Our approach successfully identified serum biomarkers associated with SS patients. The potential lipid biomarkers indicated that SS metabolic disturbance might be associated with oxidized lipids, fatty acid oxidation and energy metabolism.

Serum lipid profile, sleep-disordered breathing and blood pressure in the elderly: a 10-year follow-up of the PROOF-SYNAPSE cohort

ObjectivesDyslipidemia, sleep-disordered breathing (SDB) and hypertension are comorbid factors evidenced in adults, but poorly studied in old people. This study aimed to examine the long-term evolution of the serum lipid profile, and its relationships with SDB and blood pressure (BP) in the elderly. MethodsA ten-year follow-up of the prospective Prognostic Indicator of Cardiovascular and Cerebrovascular Events (PROOF) and the Autonomic Nervous System Activity, Aging and Sleep Apnea/Hypopnea (SYNAPSE) cohort, which initially included 1011 elderly subjects from the general population, and who were untreated by continuous positive airway pressure (CPAP). Serum lipid profile, respiratory polygraphy for SDB and ambulatory blood pressure monitoring were performed. ResultsA total of 266 subjects (male/female 150/116; age 66.2 ± 0.8 years) were reassessed after 9.6 ± 0.7 years (age 75.8 ± 1.2 years). The prevalence of high-risk dyslipidemia decreased from 61.3 to 44.4%, and hypertension from 57.9 to 27.4%. The nocturnal oxygen desaturation index increased (mean + 2.3 ± 6.7 events/hour; p < 0.001), while the mean SaO2 and minimal SaO2 decreased. These variations (Δ) of oxygen desaturation worsened whether or not elderly subjects took anti-hypertensive and lipid-lowering treatments, and were not associated with serum lipid variations. The decrease in diurnal diastolic BP was independently associated with aging, and with the lowering of the waist/hip ratio (ΔW/H) and low-density lipoprotein cholesterol (LDL-C)/high-density lipoprotein cholesterol (HDL-C) ratio, while the decrease in diurnal systolic BP only depended on aging and ΔW/H. ConclusionsThe results suggested that the observed worsening of nocturnal oxygen desaturation after 10 years in the elderly was independent of the change in circulating lipids, and not influenced by lipid-lowering treatments. However, the variation in blood pressure remained associated with aging, waist/hip and LDL-C/HDL-C ratios.Trial registry: NCT00759304 and NCT00766584 at clinicaltrials.gov.

The SRGAP2 SNPs, their haplotypes and G\u2009\xd7\u2009E interactions on serum lipid traits

Maonan nationality is a relatively conservative and isolated minority in China. Little is known about the association of the Slit-Robo Rho GTPase activating protein 2 gene (SRGAP2) single nucleotide polymorphisms (SNPs) and serum lipid levels in the Chinese populations. This study was performed to clarify the association of the SRGAP2 rs2483058 and rs2580520 SNPs and their haplotypes with serum lipid traits in the Maonan and Han populations. Genotyping of the 2 SNPs was performed in 2444 unrelated subjects (Han, 1210 and Maonan, 1234) by polymerase chain reaction and restriction fragment length polymorphism combined with gel electrophoresis, and then confirmed by direct sequencing. The allelic (rs2483058) and genotypic (rs2483058 and rs2580520) frequencies were different between the two ethnic groups. Four haplotypes were identified in our populations, and the rs2483058G-rs2580520C haplotype was the commonest one. The rs2483058C-rs2580520G haplotype was associated with an increased risk of dyslipidemia, and showed consistent association with serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), apolipoprotein (Apo) A1 levels, and the ApoA1/ApoB ratio. These results indicated that the SRGAP2 SNPs and their haplotypes were associated with serum lipid levels. Their haplotypes can explain much more serum lipid variation than any single SNP alone, especially for serum TC, HDL-C and ApoA1 levels.

Association between the MVK and MMAB polymorphisms and serum lipid levels.

Maonan ethnic group is a relatively conservative and isolated minority in China. Little is known about the association of the mevalonate kinase (MVK), methylmalonic aciduria (cobalamin deficiency) cblB type (MMAB) single nucleotide polymorphisms (SNPs) and serum lipid levels. This study aimed to determine the association between four SNPs in the MVK/MMAB and serum lipid levels. Genotyping of the rs3759387, rs877710, rs7134594 and rs9593 SNPs was performed in 1264 Maonan subjects and 1251 Han participants. Allele and genotype frequencies of the selected SNPs were different between the two populations (P < 0.05-0.001). Four SNPs were associated with high-density lipoprotein cholesterol (HDL-C) in the both ethnic groups (P < 0.0125-0.001); and one SNP with apolipoprotein (Apo) A1 (rs7134594) in Han Chinese (P <0.0125). Strong linkage disequilibria were noted among the SNPs (D'=0.63-0.96; r2=0.13-0.88). The commonest haplotype was C-C-C-T (> 50%). The frequencies of C-C-C-T, C-G-T-A, A-G-T-A, C-G-C-T, and A-C-T-A were different between the two populations (P <0.001). The associations between haplotypes and dyslipidemia were different in the Han and/or Maonan population (P < 0.05-0.001), haplotypes could explain much more serum lipid variation than any single SNP alone especially for HDL-C. Differences in lipid profiles between the two populations might partially attribute to these SNPs and their haplotypes.

Association between the DOCK7, PCSK9 and GALNT2 Gene Polymorphisms and Serum Lipid levels.

This study was to determine the association between several single nucleotide polymorphisms (SNPs) in the dedicator of cytokinesis 7 (DOCK7), proprotein convertase subtilisin/kexin type 9 (PCSK9) and polypeptide N-acetylgalactosaminyltransferase 2 (GALNT2) and serum lipid levels. Genotyping of 9 SNPs was performed in 881 Jing subjects and 988 Han participants. Allele and genotype frequencies of the detected SNPs were different between the two populations. Several SNPs were associated with triglyceride (TG, rs10889332, rs615563, rs7552841, rs1997947, rs2760537, rs4846913 and rs11122316), high-density lipoprotein (HDL) cholesterol (rs1997947), low-density lipoprotein (LDL) cholesterol (rs1168013 and rs7552841), apolipoprotein (Apo) A1 (rs1997947), ApoB (rs10889332 and rs7552841), and ApoA1/ApoB ratio (rs7552841) in Jing minority; and with TG (rs10889332, rs615563, rs7552841, rs11206517, rs1997947, rs4846913 and rs11122316), HDL cholesterol (rs11206517 and rs4846913), LDL cholesterol (rs1168013), ApoA1 (rs11206517 and rs4846913), ApoB (rs7552841), and ApoA1/ApoB ratio (rs4846913) in Han nationality. Strong linkage disequilibria were noted among the SNPs. The commonest haplotype was G-C-G-C-T-G-C-C-G (>10%). The frequencies of C-C-G-C-T-G-T-C-G, G-C-A-C-T-G-C-C-G, G-C-G-C-T-A-C-C-A, G-C-G-C-T-G-C-C-A, G-C-G-C-T-G-T-C-A haplotypes were different between the two populations. Haplotypes could explain much more serum lipid variation than any single SNP alone especially for TG. Differences in lipid profiles between the two populations might partially attribute to these SNPs and their haplotypes.

Environmental Chemicals in Urine and Blood: Improving Methods for Creatinine and Lipid Adjustment.

BackgroundInvestigators measuring exposure biomarkers in urine typically adjust for creatinine to account for dilution-dependent sample variation in urine concentrations. Similarly, it is standard to adjust for serum lipids when measuring lipophilic chemicals in serum. However, there is controversy regarding the best approach, and existing methods may not effectively correct for measurement error.ObjectivesWe compared adjustment methods, including novel approaches, using simulated case–control data.MethodsUsing a directed acyclic graph framework, we defined six causal scenarios for epidemiologic studies of environmental chemicals measured in urine or serum. The scenarios include variables known to influence creatinine (e.g., age and hydration) or serum lipid levels (e.g., body mass index and recent fat intake). Over a range of true effect sizes, we analyzed each scenario using seven adjustment approaches and estimated the corresponding bias and confidence interval coverage across 1,000 simulated studies.ResultsFor urinary biomarker measurements, our novel method, which incorporates both covariate-adjusted standardization and the inclusion of creatinine as a covariate in the regression model, had low bias and possessed 95% confidence interval coverage of nearly 95% for most simulated scenarios. For serum biomarker measurements, a similar approach involving standardization plus serum lipid level adjustment generally performed well.ConclusionsTo control measurement error bias caused by variations in serum lipids or by urinary diluteness, we recommend improved methods for standardizing exposure concentrations across individuals.CitationO’Brien KM, Upson K, Cook NR, Weinberg CR. 2016. Environmental chemicals in urine and blood: improving methods for creatinine and lipid adjustment. Environ Health Perspect 124:220–227; http://dx.doi.org/10.1289/ehp.1509693

Variation in Lipid Profile Across Different Patterns of Obesity - Observations from Guwahati, Assam.

Obesity adversely affects cardiovascular health is known. But, data is few in this regard from Assam, northeast India. The serum lipid profile is performed for cardio-metabolic status assessment. The aim of the study was to investigate variation in serum lipids across different obesity patterns in an urban population from Assam. Two hundred subjects were classified by WC (waist circumference) and BMI (body mass index) values into four groups as follows: Group I (normal WC, normal BMI), Group II (normal WC, increased BMI), Group III (increased WC, normal BMI) and Group IV (increased WC, increased BMI). WC and BMI served as measures of central and generalized obesity respectively. Lipid profile was measured using VITROS 5600 Autoanalyser, and compared across these groups. Multivariate analyses were performed separately for males and females to confirm the results of univariate analyses. WC and BMI exhibited significant correlations with different lipid parameters. Group IV individuals had the most abnormal lipid profile values, while, Group I individuals had the most normal values. Group II and Group III individuals had intermediate values. BMI was independently associated with serum triglycerides in both males and females. WC was independently associated with high density lipoprotein cholesterol in females. The lipid values varied significantly across different obesity patterns. Serum lipid concentrations were strongly influenced by anthropometric indices of obesity in both sexes. Presence of both central and generalized obesity led to greater abnormalities in lipid profile than presence of central or generalized obesity alone.

Apolipoprotein A1/C3/A5 haplotypes and serum lipid levels

Background and aimsSingle nucleotide polymorphisms (SNPs) at the apolipoprotein (Apo) A1/C3/A4/A5 gene cluster have been examined in relation to lipid metabolism and cardiovascular disease risk. However, the previous findings are...

Apolipoprotein A1/C3/A5 haplotypes and serum lipid levels

BackgroundThe association of single nucleotide polymorphisms (SNPs) in the apolipoprotein (Apo) A1/C3/A4/A5 gene cluster and serum lipid profiles is inconsistent. The present study was undertaken to detect the association between the ApoA1/C3/A5 gene polymorphisms and their haplotypes with serum lipid levels in the general Chinese population.MethodsA total of 1030 unrelated subjects (492 males and 538 females) aged 15-89 were randomly selected from our previous stratified randomized cluster samples. Genotyping of the ApoA1 -75 bp G>A, ApoC3 3238C>G, ApoA5 -1131T>C, ApoA5 c.553G>T and ApoA5 c.457G>A was performed by polymerse chain reaction and restriction fragment length polymorphism combined with gel electrophoresis, and then confirmed by direct sequencing. Pair-wise linkage disequilibria and haplotype analysis among the five SNPs were estimated.ResultsThe levels of high-density lipoprotein cholesterol (HDL-C) and ApoA1 were lower in males than in femailes (P < 0.05 for each). The allelic and genotypic frequencies of the SNPs were no significant difference between males and females except ApoC3 3238C>G. There were 11 haplotypes with a frequency >1% identified in the cluster in our population. At the global level, the haplotypes comprised of all five SNPs were significantly associated with all seven lipid traits. In particular, haplotype G-G-C-C-A (6%; in the order of ApoA5 c.553G>T, ApoA5 c.457G>A, ApoA5 -1131T>C, ApoC3 3238C>G, and ApoA1 -75bp G>A) and G-A-T-C-G (4%) showed consistent association with total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), ApoA1, ApoB, and the ApoA1/ApoB ratio. In addition, carriers of haplotype G-G-T-C-G (26%) had increased serum concentration of HDL-C and ApoA1, whereas carriers of G-G-C-G-G (15%) had high concentrations of TC, triglyceride (TG) and ApoB. We also found that haplotypes with five SNPs explain much more serum lipid variation than any single SNP alone, especially for TG (4.4% for haplotype vs. 2.4% for -1131T>C max based on R-square) and HDL-C (5.1% for haplotype vs. 0.9% for c.553G>T based on R-square). Serum lipid parameters were also correlated with genotypes and several environment factors.ConclusionsSeveral common SNPs and their haplotypes in the ApoA1/C3/A5 gene cluster are closely associated with modifications of serum lipid parameters in the general Chinese population.

Genetic, epigenetic, and gene-by-diet interaction effects underlie variation in serum lipids in a LG/J×SM/J murine model

Variation in serum cholesterol, free-fatty acids, and triglycerides is associated with cardiovascular disease (CVD) risk factors. There is great interest in characterizing the underlying genetic architecture of these risk factors, because they vary greatly within and among human populations and between the sexes. We present results of a genome-wide scan for quantitative trait loci (QTL) affecting serum cholesterol, free-fatty acids, and triglycerides in an F(16) advanced intercross line of LG/J and SM/J (Wustl:LG,SM-G16). Half of the population was fed a high-fat diet and half was fed a relatively low-fat diet. Context-dependent genetic (additive and dominance) and epigenetic (imprinting) effects were characterized by partitioning animals into sex, diet, and sex-by-diet cohorts. Here we examine genetic, environmental, and genetic-by-environmental interactions of QTL overlapping previously identified loci associated with CVD risk factors, and we add to the serum lipid QTL landscape by identifying new loci.

Effect of carnitine on serum cholesterol of alcoholic cardiomyopathy dogs

Carnitine is known to be essential for metabolism regulation in some heart diseases such as coronary heart disease. We evaluated the effect of carnitine and valsartan on alcoholic cardiomyopathy (ACM); surprisingly, it was found that carnitine leads to variations in serum lipids. The results of our study, supported by cardiac function assessment, LVW/BW ratio, hematoxylin and eosin staining, and electron microscopic morphology, not only demonstrated the validity of our ACM model but also addressed the therapeutic benefits of carnitine and valsartan in antagonizing ACM development. The alcohol group displayed a high LVEDd and low EF and FS, indicating both heart failure and cardiac remodeling. Compared with the alcohol and alcohol/valsartan groups, the concentration of serum cholesterol in the alcohol/carnitine group was significantly increased between baseline and 6 months. The body weights of dogs from the alcohol group slowly increased between baseline and 6 months, although the LV weight increased quickly. The results suggest that both carnitine and valsartan have a favorable effect on ACM. However, the fact that carnitine could increase the serum cholesterol level should lead to caution in the treatment of ACM patients who are suffering from coronary disease in the meantime.

Genetics of lipid disorders

In this review, we will highlight recent advances in identifying genes and gene regions responsible for the variation in serum lipid levels. We will also consider the next directions for research based on these advances. Large-scale genome-wide association studies have successfully screened common variants across the genome for association with serum lipids and have generated novel hypotheses about the causes of serum lipid variation. Deep sequencing of genome-wide association signals promises to expand the catalogue of variants responsible for serum lipid variation and, with a full catalogue of variants, we may develop a panel of polymorphisms with clinical utility. In parallel, functional exploration of the genome-wide association signals should expand our knowledge of lipoprotein metabolism and generate targets for pharmacologic intervention.

Influence of SCARB1 polymorphisms on serum lipids of hypercholesterolemic individuals treated with atorvastatin

The SR-BI is a key component on the cholesterol metabolism. Polymorphisms in the SR-BI gene (SCARB1) were related with variations on plasma lipoprotein profile and other risk factors for cardiovascular disease. We tested the relationship of 3 SCARB1 single nucleotide polymorphisms (SNPs) with hypercholesterolemia in a Brazilian population and whether these variants can influence lipid-lowering response to atorvastatin. c.4G>A, c.726+54C>T and c.1050C>T SNPs and serum concentrations of lipid and apolipoproteins were evaluated in 147 hypercholesterolemic (HC) and 185 normolipidemic (NL) unrelated Brazilian subjects. HC patients were treated with atorvastatin (10 mg/day/4 weeks). Frequencies of SCARB1 polymorphisms were similar between the HC and NL groups (p>0.05). The T allele for c.726+54C>T was associated with higher LDL-c in NL and with higher apoB and apoB/apoAI in HC (p<0.05). HC individuals carrying c.1050C allele carriers (CC and CT genotypes) had lower change of total cholesterol, LDL-c, apoB and apoB/apoAI ratio (p<0.05) than the TT genotype carriers in response to atorvastatin. The SCARB1 polymorphisms are related with variations in serum lipids in the Brazilian population and c.1050C>T SNP is associated with lipid-lowering atorvastatin response.

Genetic and environmental influences on serum lipids and the effects of puberty: a Chinese twin study

To study the contribution of genes and environment on the variation of serum lipids and the effects of puberty. In total, 314 same-sex twin pairs aged 5-18 years were studied. Puberty was marked physiologically by spermarche/menarche, and model fitting was used to analyse the genetic and environmental variance and its difference before and after puberty. Lipid levels were different before and after puberty. The genetic factor had an important influence on lipid levels; the heritability estimates of total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), lipoprotein(a) (Lp(a)) and apolipoprotein E (ApoE) were between 49 and 86%. The total phenotypic variances of TC, HDL, LDL, Lp(a) and ApoE decreased after puberty, mainly as a result of decrease of genetic variance, even though the common environmental variance for HDL, Lp(a) and ApoE increased. Genes and the environment have different effects on the levels of different lipids. The shared environmental effects on lipids are very important in children. The role of puberty on lipids deserves future study.

Paraoxonase (PON1) is associated with familial combined hyperlipidemia

Familial combined hyperlipidemia (FCH) is a common genetic lipid disorder of which the molecular basis still remains to be elucidated. Since the HDL-associated enzyme serum paraoxonase (PON1) is associated with variation in serum lipids and lipoproteins, we determined whether variation in PON1 also contributes to the FCH phenotype. The study population consisted of 32 well-defined families with FCH, including 103 FCH patients and 240 normolipidemic relatives (NLR). In addition to plasma lipids and lipoproteins we determined PON1 activity (arylesterase- and paraoxonase activity) as well as the common genetic variants −107C > T, 55L > M and 192Q > R in the PON1 gene. The arylesterase activity was significantly higher in FCH patients when compared to NLR ( P < 0.001). In the total population, the PON1 genetic variants associated with the highest arylesterase activity (−107CC and 55LL) also associated with higher levels of total cholesterol, apolipoprotein B, triglycerides and VLDL-cholesterol and decreased levels of HDL-cholesterol. In support, the combination of the −107CC with the 55LL genotype associated with a significant increased risk for FCH when compared to the −107TT/55MM genotype (odds ratio 5.0 (95% CI, 1.3–19.1, P = 0.02)). In conclusion, in this population of subjects from well-defined families with FCH, PON1 is biochemically and genetically associated with FCH.