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BackgroundFamilial hypercholesterolaemia (FH) leads to premature coronary artery diseases (CAD) which pathophysiologically can be measured by inflammation, endothelial activation and oxidative stress status. However, the status of these biomarkers among related unaffected relatives of FH cases and whether FH is an independent predictor of these biomarkers have not been well established. Thus, this study aims to (1) compare the biomarkers of inflammation, endothelial activation and oxidative stress between patients with FH, their related unaffected relatives (RUC) and normolipaemic subjects (NC) (2)determine whether FH is an independent predictor of these biomarkers.MethodsOne hundred thirty-one FH patients, 68 RUC and 214 matched NC were recruited. Fasting lipid profile, biomarkers of inflammation (hsCRP), endothelial activation (sICAM-1 and E-selectin) and oxidative stress [oxidized LDL (oxLDL), malondialdehyde (MDA) and F2-isoprostanes (ISP)] were analyzed and independent predictor was determined using binary logistic regression analysis.ResultshsCRP was higher in FH and RUC compared to NC (mean ± SD = 1.53 ± 1.24 mg/L and mean ± SD = 2.54 ± 2.30 vs 1.10 ± 0.89 mg/L, p < 0.05). sICAM-1 and E-selectin were higher in FH compared to NC (mean ± SD = 947 ± 742 vs 655 ± 191 ng/mL, p < 0.001 and 175 ± 131 vs 21.6 ± 10.7 ng/mL, p < 0.001 respectively) while sICAM-1 concentration was higher in RUC compared to NC (mean ± SD = 945 ± 379 vs 655 ± 191 ng/mL, p < 0.01). Biomarkers of oxidation (ox-LDL, MDA and ISP) were elevated in FH compared to NC [mean ± SD = (48.2 ± 26.8 vs 27.3 ± 13.2 mU/L, p < 0.001), (2.57 ± 1.3 vs 1.20 ± 0.30 nmol/mL, p < 0.001) and (645 ± 396 vs 398 ± 20.5 pg/L, p < 0.001) respectively], but no significant differences were observed between RUC and NC (p > 0.05). FH was an independent predictor for sICAM-1 (p = 0.007), ox-LDL (p < 0.001) and MDA (p < 0.001) while RUC independently predicted for sICAM-1 (p < 0.001).ConclusionThe screening for FH is vital as all biomarkers associated with atherogenesis are higher in these subjects and FH also independently predict biomarkers of endothelial activation and oxidative stress. Furthermore, despite not fulfilling the diagnostic criteria for FH, related unaffected family members that may not phenotypically express the mutation may still be at risk of developing CAD as reflected from the enhanced inflammatory and endothelial activation status observed in this group. This highlights the need to not only conduct family tracing in indexed FH cases, but also assess the coronary risk among family members that do not fulfil the FH diagnostic criteria.

Background: Autosomal dominant hypercholesterolaemia (ADH) is a genetic disorder that is mainly resulted from defects in the lowdensity lipoprotein receptor (LDLR) and apolipoprotein B-100 (APOB-100) genes. Few studies of familial hypercholesterolaemia (FH) have been conducted in Malaysia, that makes the underlying main defect remains not well understood.Objectives: This study was aimed to describe the molecular aspects of FH among Malaysian subjects. Methods and Findings:We studied a group of 74 familial hypercholesterolaemic patients and 77 healthy control subjects. The promoter region and the 18 exons of the low-density lipoprotein receptor gene were screened by denaturing high-performance liquid chromatography (DHPLC) to detect small deletions, insertions and nucleotide substitutions, while DNA sequencing was applied to look for gene variants in amplicons of exon 26 and 29 in the APOB-100 gene. A total of five gene sequence variants in the LDLR gene were reported in 54.1% of the studied patients. P.Arg471Arg variant has the highest frequency of 20.3% among the study subjects. One intronic mutation (c.313+1G>A) and one missense mutation (p.Arg 385Try) were found to be pathogenic, while the other three variants were reported to be non-pathogenic by the in silico analyses. Nine variants were reported in the APOB-100 gene among familial hypercholesterolaemic patients with a non-significant difference in their frequency from the control subjects.