Genetic and Common Environmental Contributions to Familial Resemblances in Plasma Carotenoid Concentrations in Healthy Families

Abstract

Carotenoids have shown an interindividual variability that may be due to genetic factors. The only study that has reported heritability of serum α- and β-carotene has not considered the environmental component. This study aimed to estimate the contribution of both genetic and common environmental effects to the variance of carotenoid concentrations and to test whether their phenotypic correlations with cardiometabolic risk factors are explained by shared genetic and environmental effects. Plasma carotenoid concentrations (α-carotene, β-carotene, β-cryptoxanthin, lutein, lycopene, zeaxanthin, and total carotenoids) of 48 healthy subjects were measured. Heritability estimates of carotenoid concentrations were calculated using the variance component method. Lutein and lycopene showed a significant familial effect (p = 6 × 10−6 and 0.0043, respectively). Maximal heritability, genetic heritability, and common environmental effect were computed for lutein (88.3%, 43.8%, and 44.5%, respectively) and lycopene (45.2%, 0%, and 45.2%, respectively). Significant phenotypic correlations between carotenoid concentrations and cardiometabolic risk factors were obtained for β-cryptoxanthin, lycopene, and zeaxanthin. Familial resemblances in lycopene concentrations were mainly attributable to common environmental effects, while for lutein concentrations they were attributable to genetic and common environmental effects. Common genetic and environmental factors may influence carotenoids and cardiometabolic risk factors, but further studies are needed to better understand the potential impact on disease development.

Weighted gene co-expression network analysis to explain the relationship between plasma total carotenoids and lipid profile

“…A total of 48 Caucasian French-Canadian subjects from 16 families were recruited in the greater Quebec City metropolitan area, in Canada, as part of the GENERATION Study. The GENERATION Study was designed to evaluate familial resemblances in omics (DNA methylation [55] and gene expression [56]) and metabolic (metabolites [57] and carotenoids [7]) profiles in healthy families and to test the impact of these profiles on cardiometabolic health. Families were composed of 16 mothers, 6 fathers, and 26 children.…”

“…Samples and standards used for the measurement of carotenoid concentrations were prepared as reported previously [7]. Briefly, 100 μL of fasting plasma samples were thawed a few hours before analysis.…”

“…High-performance liquid chromatography (HPLC)-UV analysis was performed using an Agilent 1260 liquid handling system (Agilent, Mississauga, Ontario, Canada) as described previously [7]. Carotenoids were separated with a mobile phase consisting of methanol to water (98/2, v / v ; Eluent A) and methyl-tert-butyl ether (MTBE; Eluent B; VWR, Mississauga, Ontario, Canada).…”

“…Plasma HDL-C concentrations also mediated the observed sex difference in serum carotenoids in Caucasian individuals [5]. Correlations were observed between α- and β-carotene and HDL-C and triglyceride (TG) concentrations [6] and between β-cryptoxanthin and zeaxanthin and TG in a previous study by our group [7]. The NHANES 2003–2006 study also reported that several serum carotenoids positively correlated with HDL-C concentrations [8].…”

Network Analysis of the Potential Role of DNA Methylation in the Relationship between Plasma Carotenoids and Lipid Profile

“…Lower circulating carotenoid concentrations are associated with lower plasma total cholesterol (TC), LDL-cholesterol (LDL-C), and HDL-cholesterol (HDL-C) concentrations [6]. Moreover, α- and β-carotene correlated with HDL-C and triglyceride (TG) concentrations [7], while β-crytoxanthin and zeaxanthin correlated with TG concentrations in a previous study by our group [8]. Thus, several studies have observed associations between circulating carotenoids and plasma lipid concentrations, which are both transported by lipoproteins [9].…”