title: Genetic determinants of risk factors for cardiovascular disease in a population from rural Brazil.
abstract: We investigate the heritability of and pleiotropic relationships among triglycerides and cholesterol lipoproteins that have long been considered traditional risk factors for cardiovascular disease. Quantitative lipid and lipoprotein phenotypes were determined for a cross-sectional sample of a community in Jequitinhonha valley in northern Minas Gerais state, Brazil. The sample consisted primarily of subsistence farmers. Two hundred sixty-nine individuals (128 males and 141 females), ages 18-88 years, were sampled. Eighty-eight percent (n = 252) of the individuals belonged to a single pedigree, which was highly informative for genetic analysis. Data on anthropometrics, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol, and triglycerides were available for each study participant. Extended pedigrees were constructed using the pedigree-based data management software PedSys. Univariate and bivariate variance-components analyses, adjusted by sex and age, were performed using the SOLAR software package. Heritability estimates of lipids and lipoproteins ranged from 29% to 45% (p < 0.008). The highest heritability estimated was for HDL-C (h2 = 44.8%, p < 0.0001), and this was the only trait that exhibited a significant household effect (c2 = 25%). Strong positive genetic correlations were found between triglycerides and very low density lipoprotein (VLDL) (rhog = 0.998) and between total cholesterol and LDL-C (rhog = 0.948). Significant genetic correlations were also found between triglycerides and LDL-C, between total cholesterol and VLDL, and between total cholesterol and LDL-C and VLDL, and finally between LDL and VLDL. There was a significant negative environmental correlation between triglycerides and HDL-C (rhoe = -0.406).
authors.affiliation: Department of Maternal and Child Nursing and Public Health, School of Nursing, Universidade Federal de Minas Gerais, Avenida Alfredo Balena 190, Belo Horizonte, MG 30130-100, Brazil.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Velásquez-Meléndez
authors.forename: Flavia C
authors.initials: FC
authors.lastname: Parra
authors.forename: Andrea
authors.initials: A
authors.lastname: Gazzinelli
authors.forename: Sarah
authors.initials: S
authors.lastname: Williams-Blangero
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Correa-Oliveira
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil / Q000453:epidemiology; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000235:genetics*; D008076:Cholesterol, HDL / Q000235:genetics; D008078:Cholesterol, LDL / Q000235:genetics; D003430:Cross-Sectional Studies; D016021:Epidemiologic Studies; D005260:Female; D005828:Genetics, Population; D006801:Humans; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D010641:Phenotype; D012307:Risk Factors; D012424:Rural Population; D011795:Surveys and Questionnaires
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL