Apolipoprotein E gene polymorphisms in Lebanese with hypercholesterolemia

Inherited Thrombophilia Associated With Ischemic Pediatric Stroke in Parent-Child Pairs

BACKGROUND

We aimed to examine inherited thrombophilia frequencies by extending genetic profile to previously rarely or not investigated polymorphisms in children with ischemic pediatric stroke (IPS) and their parents.

METHODS

The study included 33 children: 23 with perinatal arterial ischemic stroke (PAIS), eight with childhood arterial ischemic stroke (CAIS), and two with sinovenous thrombosis and their parents (33 mother-child, 12 father-child, and 12 mother-father-child pairs). Genotyping of FV-Leiden, FV-H1299R, FII-G20210A, β-fibrinogen-455G>A, FXIII-A-Val34Leu, PAI-1(4G/5G), HPA-1, MTHFR-C677T, MTHFR-A1298C, ACE(I/D), and APOE(ε2-4) was performed using CVD Strip assay (ViennaLab, Austria).

RESULTS

At least one and up to seven simultaneously present polymorphisms were observed in all children with IPS, mothers, and fathers. More than five simultaneously present polymorphisms were identified threefold more frequently in children with IPS (10 of 33; 30%) compared with the child control group (17 of 150; 11%), yielding a statistically significant difference between the two groups (odds ratio [OR] = 3.40; 95% confidence interval [CI] = 1.39 to 8.35; P = 0.012). Stronger association was revealed for PAIS (OR = 4.17; 95% CI = 1.55 to 11.29; P = 0.008) and CAIS subgroups (OR = 7.82; 95% CI = 1.79 to 34.20; P = 0.012). Complete match of polymorphisms was not identified in any parent-child pair. A partial match (one to four mutual polymorphisms) was found in 11 of 12 parent-child pairs where until three mutual polymorphisms was present in 11 of 12 (91.7%) father-child compared with 21 of 33 (63.6%) mother-child pairs.

CONCLUSIONS

According to obtained results the simultaneous presence of more than five polymorphisms is associated with a higher risk for IPS occurrence, suggesting the risk enhancement for PAIS in the presence of pregnancy complications or for CAIS in conjunction with maternal comorbidity and positive family history. The presence of up to three mutual polymorphisms more frequently in father-child than mother-child pairs suggests significant paternal contribution of inherited thrombophilia to increased risk of IPS.

APOE genotypes in Lebanon: distribution and association with hypercholesterolemia and Alzheimer's disease

AIM

We first investigated the distribution of APOE genotypes in Lebanese general population and Alzheimer's disease study (ADS) groups, and compared it with 1000 genomes populations. Then, we assessed eventual association between APOE genotypes, hypercholesterolemia and Alzheimer's disease (AD).

MATERIALS & METHODS

This cross-sectional study was conducted on 591 individuals. Clinical and biological data were collected, DNA was extracted and genotyped using Kompetitive allele specific PCR (KASP™) and PCR-restriction fragment length polymorphis (PCR-RFLP). Results: Prevalence of APOE genotypes in Lebanon was similar to that seen in Asian populations. APOE genotypes were not associated with hypercholesterolemia. A significant difference between APOE genotypes in AD cases versus controls and versus Lebanese general population was seen. Moreover, E4 allele was approximately threefold higher in Alzheimer's disease study patients when compared with the remaining individuals.

CONCLUSION

We established the distribution of APOE genotypes in the Lebanon and showed that in contrast to lipid profile, E4 correlates with AD.

Significance of the use of the ViennaLab "Cardiovascular Disease panel" (CVD) Assay as a reflex test for the "Factor V/II/MTHFR Assay"

Introduction

Trends toward identifying risk factors of thrombotic complications had become essential as an attempt to prevent and decrease the incidence of the complications. Thrombosis has been associated with predisposing factors like mutations in FV, PTH, MTHFR and other genes.

Aim

Evaluate whether the CVD StripAssay has an added value in the screening for more thrombophilia risk factors, which may predispose for the development of cardiovascular diseases and other thrombotic clinical conditions.

Methods

We compared the results for 94 patients who were previously tested for Factor V, Factor II and MTHFR gene mutations using the ViennaLab FV-PTH-MTHFR StripAssay, and for whom additional testing for the Cardiovascular Disease panel (CVD StripAssay, ViennaLab) was requested.

Results

Using the CVD StripAssay, 66% of patients who had no mutations when tested using the FV-PTH-MTHFR StripAssay or carried a mutation for MTHFR, were found to have additional genes' SNPs or mutations that are highly associated with a risk of thrombosis as per the available international literature.

Conclusion

This observation is of extreme importance in clinical practice for the introduction of the extended CVD panel into routine molecular diagnostic test menus and highlights the importance of genetic analysis of the implicated genes in the management of patients with a thrombotic episode presentation.

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First paper in the literature that compares the use of two assays to detect mutations in genes involved in thrombosis.

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The common genes involved in thrombosis may not be enough alone to consider a patient “negative” for genetic predisposition.

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Molecular diagnostics laboratories should consider expanding their services to include a more extensive genetic thrombophilia profiling.

Elevated Levels of LDL-C are Associated With ApoE4 but Not With the rs688 Polymorphism in the LDLR Gene

INTRODUCTION

Apolipoprotein E (ApoE) 4 isoform has been associated with elevated levels of cholesterol, low-density lipoprotein cholesterol (LDL-C), and triglycerides (TGs), meanwhile several polymorphisms in the LDL receptor (LDLR) gene have been associated with increased levels of total cholesterol and LDL-C.

MATERIAL AND METHODS

We studied 400 women from Southwest Mexico. Anthropometric features and biochemical profile were evaluated, and genotyping of single nucleotide polymorphisms rs429358 and rs7412 in the APOE gene and rs688 in the LDLR gene was determined by TaqMan assays.

RESULTS

We found significant association between LDL-C (odds ratio [OR] = 3.3, 95% confidence interval [CI]: 1.9-5.7) and marginal association with TG (OR = 1.7, 95% CI: 1.0-2.9) of atherogenic risk in women carriers of the ApoE4 isoform compared to ApoE3. The TT genotype of rs688 in the LDLR gene was not found to be associated with elevated levels of total cholesterol or LDL-C.

CONCLUSION

Our results show that carrier women of the ApoE4 isoform are more likely to have elevated levels of LDL-C and therefore increased risk of developing atherosclerosis.